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Because wasting time on transpiration also kills, small slices of lost life in parallel.

Traffic had long hanging fruit for saving lives for sure -- mandatory daytime running lights come to mind as a zero cost improvement -- but the speed equation is not generally simple.

> small slices of lost life

"A micromort (from micro- and mortality) is a unit of risk defined as one-in-a-million chance of death."

I think they were talking about time, not risk.
>Because wasting time on transpiration also kills, small slices of lost life in parallel.

So you're willing to put other people at risk, for an immeasurable gain to yourself?

Maybe you should take public transport more, where you can actually do something else while being transported?

> So you're

Comments here need to follow the HN guideline which asks: "Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize."

https://news.ycombinator.com/newsguidelines.html

Based on my experience with other people, both in and out of traffic, that is the most plausible interpretation.
That's not what the guideline is asking for. If it were, it would be a no-op, since that would be asking for one's first interpretation, and we get that anyway.
"Assume good faith" is a tall order, when you have to deal with people everyday.
Yes. Air travel is quite safe, for example, but not danger-free. We as a society are willing to accept some death here and there so that the rest of us can go on interesting vacations.
> mandatory daytime running lights come to mind as a zero cost improvement

Jury's out on that one. If you're always looking for vehicles with lights on, you're less likely to notice pedestrians or cyclists in the road.

Quite an interesting article.

My beef is also with car manufacturers. I have a bog standard 2015 Mazda 3. The speedometer reads up to 260KMH, the national speed limit in the country is 100KMH, who the fuck are they designing these things for?

The national speed limit doesn't apply when on a race track.
Can you imagine at the dealership:

You step into a basic Toyota, you gauge the speedometer. It reads 0 on end, 160 on the other.

Next you step into a basic Honda, you gauge the speedometer. It reads 0 on one end, 80 on the other.

Which one will most people buy, all other things being equal?

Now, if you want to have an absolute maximum speed, governments can insist on tamper-proof governors. Kinda like Singapore does for its cabs.

> ...who the fuck are they designing these things for?

Obviously you since you own the thing.

If people didn't buy the fast cars they wouldn't build the fast cars...how many Beetles were sold worldwide and those things could barely do 110kph with a good tailwind?

Aren't all of the gauges from speed, temperature, tach, fuel, etc. meant to show engineering ranges and not optimal ranges? If you designed a car that couldn't go faster than 100KMh, I assume driving it 100% of the time at 100kmh would be more detrimental to the car's longevity than operating a more capable car at a lower percentage of its capability.

I realize I'm making some assumptions here, but maybe the maximum speed of a car is an design artifact of maximizing for multiple variables (longevity, fuel consumption, maintenance costs), not just speed.

I'm not an engineer so I have no idea what I'm talking about.

I believe the European base model Mazda3 has a 1.5L engine with 99 HP. If that is the one we are talking about, or even the 2.0L engine with somewhat more, then 260KMH is not remotely related to the engineering capability, with or without a speed governor. I'd assume it's just the standard gauge for all their cars.
I have some thoughts on why this is the case.

First, speed limits vary from place to place and manufacturers don't need to change the speedometer for each one. For instance, in the US, there are places where the limit is as high as 137KMH, and it used to be unlimited in places. I don't know what Germany is like these days.

Also, the Mazda3 is said to have a governed top speed of 190KMH* so the speedometer reading up to 260 is a red herring with respect to actual performance.

Finally, a high top speed is a side effect of having the acceleration that consumers would like.

*It's a governed speed in order to preserve the tires, but it's unlikely it would make 260KMH even without the governor; maybe 200-220KMH at best - see https://en.wikipedia.org/wiki/Mazda3

I don't know what Germany is like these days.

Large portions of the Autobahn are still unlimited.

They are, although over the last decade the amount of people driving above 180kph seems to have gotten less. It has gotten more busy on the road, and a government campaign promoting safe driving which seems to have had effect.
I've observed the same thing. It feels much rarer that people drive very fast on the autobahn these days.

This being said, I always assumed this was mostly an effect of a) many cars being able to show fuel consumption on the hud and b) fuel prices having risen considerably.

Top speed doesn’t directly correspond with acceleration, as weight plays a factor as well. To pick a slightly extreme example, Caterham’s Seven 160 will accelerate from 0-60mph in 6.9s yet tops out at 100mph, due to a sub-500kg weight and an 80bhp engine: http://uk.caterhamcars.com/cars/seven-160
Implicitly I was referring to a given car model, which isn't going to have that much variation in weight.
who the fuck are they designing these things for?

The Germans.

The max value of the speedometer is irrelevant, the max speed of Mazda 3 (depending on the engine) is ~210 km/h. On a flip note the value of top speed should in the car manual. Read the doc :)

There are countries with higher limits as well, i.e. they have not designed to be sold in your own country solely.

It's marketecture. (marketing/architecture)

You don't actually need it, but if you can be convinced you need it or want it, then you'll pay more for it. Most people don't buy cars based purely on practicality. They buy the car for the lifestyle they wish they had.

And dammit I wanna be a race car driver!

It's a UI thing.

Most of them set a range so the standard operating speed on a highway is roughly at the top of the gauge. In this way, people can gauge their speed when driving different vehicles my glancing at the position not reading the numbers.

1. modern cars have digital speedometer display

2. many cars don't have a linear (circumferential) scale on the analogue display (because they put the "highwy speed" at the top of the semi-circle

Interesting article. One can easily notice that most folks seem to treat the speed limit as a minimum speed rather than a maximum speed. It's not just designers designing for speed. They do so because of market demand. That demand is boosted by advertising - both overt and culturally pervasive imagery. Buckle up folks. Try not to speed. You're really not saving much, if any, time. Also minimize left turns and lane changes. When you do turn (or change lanes) always use your turn indicator. When cars are robots they can do these things. The worry it that freedom loving consumers will still choose thrills over safety and this may stunt the adoption of robocars.
Cars are actually quite safe if you consider how much we use them. Your odds of dying in a car accident are quite low. Given that robocars have their own trade-offs, I don't think it's too surprising that some people will elect to continue to buy human-driven cars indefinitely if given the choice.
My odds of dying in a car are much higher then almost anything else in the short term. If there is anything to rationally optimize for, it is car safety.
I think maybe you are missing a whole bunch of other risks in your life that are more likely to take your life.

How much do you worry about dying from a fall, or poison, or alcohol, or drugs? Or a firearm? All of those are either similar to or more likely than dying in a car accident.

If you want to rationally optimize for something that will improve your survival odds, heart health is by a vast, vast margin a better place to spend your efforts.

If you drive an average number of miles per year, you will probably be involved in some kind of accident once every decade. The odds you will die in that accident are pretty low, as it only happens about once every 100,000,000 miles driven.

They may be 'safe' for the people in the car, but not for the people who get hit.

It's cars crashing into bicycles, pedestrians or buses (causing the buses to avoid them and crash) that are the major issue.

The people who die in car crashes are innocent healthy people. Often killed by people who never think how dangerous cars are and assume that they themselves are safe.

One of the major bus crashes [0] was caused by a drunk SUV driver over taking a bus too fast in the rain, losing control, crashing into the bus and killing numerous passengers. The SUV driver only suffered slight injuries.

[0]: https://en.m.wikipedia.org/wiki/Benalm%C3%A1dena_coach_crash

Ah, yet another Strong Towns anti-car screed of "let's make all roads so damn slow nobody can actually get anywhere" without any discussion of the downside of what they propose.

I've lived in "Cannah get theyah from heah" Boston. I can assure you that slow, safe, crappy, narrow, winding roads suck as bad as you think.

Or try going from Braddock to Penn Hills in Pittsburgh, PA. Nice and slow and infuriating. There's a reason why a whole bunch of people decided "You know, that nice empty area west of Pittsburgh with roads that actually let you get from A to B is very enticing."

> One can easily notice that most folks seem to treat the speed limit as a minimum speed rather than a maximum speed.

I disagree. People simply IGNORE the speed limit and drive at what they consider to be a safe speed.

Part of the problem is that there are political forces (cough police budgets) that encourage stupidly low speed limits. If all roads were set at the appropriate speed (something like 85% of traffic, IIRC, but there is an actual engineering number), suddenly "speeding" becomes an actual traffic safety issue.

And, in fact, ignoring a speed limit is a rational decision when everybody else would be going 10-20mph faster than you. Absolute speed means more damage when a accident occurs, but relative speed differentials mean more accidents occur.

Didn't read? That 85% _mantra_ is mentioned. Yes, it's an engineering principle...designed for rural roads. Blindly applying that to all other road types is not engineering, that's cargo cult.
Can someone please explain the 85% thing to me? I've read both the comments and article and still don't fully understand what it is. Maybe I'm stupid.
Not 85%, but 85th percentile, apparently.

https://metrocount.com/downloads/flyers/Speed_analysis_1.pdf

I'm not a traffic engineer so I'd love an explanation, because on the first look, it seems absurd to apply this measure to determining speed limits, as a) 85th percentile will keep creeping up with each iteration of such speed limit adjustment, and b) the whole rationale seems to depend on "wisdom of the crowds", i.e. trusting greedy optimization to find the right balance in the system that needs to be optimized globally.

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> a) 85th percentile will keep creeping up with each iteration of such speed limit adjustment,

That doesn't actually occur. In 1997, West Virginia raised its speed limits from 55 to 65 mph on limited access 4 lane divided highways. The 85th percentile speed incrased from 62 mph to 66.5 mph. The compliance level with the speed limit went from 15% to nearly 85%. On interstate highways, the speed limit increased from 65 mph to 70 mph. The 85th percentile speed increased from 70 mph to 71.6 mph. The compliance rate went from 50% to about 70%.

In both cases, the compliance rate went up (in one case, substantially). Also, the Martin Parker study [1] also says that lowering and raising speed limits do not substantially affect actual traffic speeds.

[1] https://www.ibiblio.org/rdu/sl-irrel/index.html

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> People simply IGNORE the speed limit and drive at what they consider to be a safe speed.

And a lot of people are completely incapable of determining what is actually a safe speed.

> One can easily notice that most folks seem to treat the speed limit as a minimum speed rather than a maximum speed.

That's because the speed limit doesn't match actual traffic speeds. On highways/motorways, traffic typically will freely flow at speeds ranging from 75 to 85 mph (120 to 140 km/h). Posting a speed limit of 55 to 65 mph (90 to 110 km/h) will result in traffic treating those numbers as a minimum acceptable speed.

In fact, in the state of Virginia (in the USA), they have signs posted on their interstate highways that state that commercial vehicles may not use the left most lane if being operated below the posted speed limit (65 or 70 mph).

Surely this is tautological? People don't obey the speed limit because the speed limit doesn't match the speed they're going at?
>However, a majority of the severe injury and fatal collisions are preventable, so they are not accidents

100% of transportation-related incidents are preventable, full stop. You can always stay home. Beyond that, it's a question of how we balance a number of factors such as risk and quality of life.

Also, where does the author get the idea that preventable is an antonym of accidental?

Just because someone failed to take certain steps to prevent an accident, it doesn't mean that they deliberately caused the accident.

I've got a guess as to what the author is talking about, because gun owners have a similar thing. In the case of guns, it's "there's no such thing as an accidental discharge, only a negligent one".

By this reading, the author is probably saying that unless your car malfunctions and prevents you from stopping or steering, or there is some equivalent fluke happening (a deer darts out in front of you and you physically can't stop in time), then "accidents" are caused by negligence (not checking lanes when changing, playing with the radio, not looking for pedestrians) or malfeasance (unsafe passing, driving at an unsafe speed for the conditions, drunk driving).

I have mixed feelings about this, but I've been driving a while and I've seen a lot of truly stupid and/or mean spirited and/or reckless behavior that could quite predictably result in a collision, but it'd be a stretch to call the sad and obvious outcome an 'accident'.

It then goes on to say

> What is your state or city doing to address this safety issue and prevent severe injuries and fatalities?

So the negligent party is implied not to be the individual driver who is not giving due care and attention, but the road designer or maintainer for not making the road safer.

I agree that crashes often occur due to the direct negligence of a road user, but when it comes to the state, there are a lot of tradeoffs and calculations to make. They are not responsible for each individual accident, but for the overall outcome of road use in general. It's erroneous to say the state is negligent for (e.g) funding emergency services to improve outcomes after a range of incidents both on and off the road, vs. Road safety measures. If £X of extra ambulance and fire funding prevents Y road-related deaths and Z other deaths, whilst that same sum on road safety measures only prevents those Y road deaths, then cure may be better than prevention.

This is my biggest gripe with all these "safe driving" articles. They never evaluate the cost/benefits of driving in a more safe manner of which there are many.
Not necessarily. It's not so unusual for a vehicle to be driven off the road and into a private house or garden. Sometimes this is fatal for the people in the house.
Yes, but it would be preventable if the driver also stayed at home.
Japan runs with somewhat lower speed limits.

The article is heavy on Celebration, FL, which was built by Disney, but has fallen on hard times. It's deliberately retro idealized 1950s America, and entirely privatized. That's a very unusual community.

The optimal speed for maximum traffic flow is around 35mph. Faster than that, and the cars space out further and throughput decreases. Slower than that, and not enough cars per second are passing. Metering signals are designed to throttle entry to the freeway to keep speed around 35mph.

Living in Japan, I'm not sure I would say that the slower speeds make things safer (can't say one way or another). However, it definitely changes the way you think about geography.

I spent about 12 years of my adult life living in Ottawa Canada and about 8 years living in Japan (with the balance being in the UK). In Ottawa, I would not think twice about driving 20-30 km to hang out with my friend after work. When all is said and done, it's under an hour of driving for a round trip. But in Japan, 30 km away might as well be on the other side of the moon for me most days. From where I live, the nearest "big" city (of 700K people) is 25 km. To drive there would take over an hour each way. The bus fare is over $20 US, round trip (and takes 3 hours round trip).

I stay in my town. I walk to the izakaya (neighbourhood pub). I walk to the super market. I walk to the hardware store. I walk everywhere -- anything I would want to go to is less than 2 km away.

Not everybody lives the way I do, but enough people do that each town has it's own flavour. It has it's own special foods and shops. I can ride my bike 5 km to the next town over and it's different than the town I live in. I can go another 5 km and that town is also different.

Compared to Canada, it's night an day. In Canada, it would take me 5 km just to get out of my housing subdivision. Walking to the grocery store is a crazy thought unless you just happened to live next to a grocery story. Don't get me wrong -- Ottawa is a great place, but you really need to live in the older areas to get much flavour. The rest is cookie cutter subdivisions, interspersed with malls.

Having said that, I'm not sure if it's reasonable to expect to transplant a non-car culture into NA. The vast majority of my friends in Canada dream of owning a home with enough land that they never have to see their neighbours. They don't wan't a neighbourhood where they walk everywhere. They want a kind of island and they really don't mind driving from island to island. It's not for me, but I can definitely understand the appeal.

> They don't wan't a neighbourhood where they walk everywhere. They want a kind of island and they really don't mind driving from island to island. It's not for me, but I can definitely understand the appeal.

That's interesting. Sometimes it feels like "modern city" advocates are super extrovert narcissists who want everyone to live in crammed spaces with many people around. And then optimise for that. They're willing to sacrifice space for their needs

Yet many people legitimately want to live sparsely and are willing to sacrifice other things for space.

That might be a kind of extreme position, but I think you're right that they would be looking for slightly higher population densities in general. In Japan it's kind of forced on people because the country is so mountainous. You only have so much flat space to work with and you have to balance the needs of living, farming and manufacturing. People who want to live all by themselves can move up into the mountains where you are basically surrounded by nature.

For me, I live in a small town. There are about 20K people in this area, although the official city is quite a bit bigger (it encompasses 3 towns and the intervening mountains for efficient administration purposes). I live in an apartment building, but that building is literally in the middle of a rice field. The whole town is a mix of farms, tea fields, manufacturing plants (including some very famous ones, even though we are in the middle of nowhere) and houses. Even though a lot of people refer to this town as being sh*t rural (literal translation -- kuso inaka), it actually has a population density of a typical suburban neighbourhood in North America. Even with that population density, I can walk for 20 minutes or so and be in a nature preserve where nobody lives.

This is pretty typical here. Farms are small. People live in towns and villages that are fairly tightly packed and surrounded by mountains. Even in fairly large cities (say around 700K or so), it won't take you more than about 15 minute of walking from the inner city to hit your first farm.

I know a lot of people love big city life, but I'm not one of those people. I like living in a neighbourhood that is self contained and has a local flavour. I like knowing my neighbours and seeing them daily as they walk or bike to work (again fairly unique Japanese culture -- most people never change jobs, so they can easily live near their workplace). Even more, I like travelling and exploring my surroundings because there is something interesting in every nook and cranny. Ironically, the difficulty in travel and the geographical separation of towns makes it possible to to "travel" 10 km and be a tourist.

I personally think that the people advocating the "modern city" are on the right track, even if I don't always agree on everything. However, I can understand why it is a hard sell in Canada and the US (I shouldn't lump in Mexico here, because I know nothing about it).

It's a hard sell not only in Canada or US, quite a bit of Europe has more than enough space as well. "Modern city" is good you want to optimise for dense living and certain lifestyles. Yet it fails for quite a few people and then quite a bit of it doesn't make sense. I guess the solution would be to design cities to allow both kinds of people to leave at peace. Personally I like German model. Dense urban centers with liveable country side. Looks like both kinds of people are pretty happy and they can sustain quite a lot of population too.
maximum traffic flow only matters during times of congestion. Off-peak, congestion isn't a factor.
... because speed is... fun? :-)
The one issue I have with the article is that the author doesn’t mention specifics about designing streets to lower the speed. Is the implied suggestion to make roads terribly curved so it’s really hard to drive fast? That seems to have it’s own drawbacks. I was surprised the author didn’t mention that many cities have intersections designed so that cars trying to turn right with a green light often intersect with a crosswalk that is also green for pedestrians. That seems more amiable to redesign rather than the grid road designs favored in most cities.
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I believe the author is advocating for "traffic calming" measures, which are a fairly standardized set of measures that urban planners and developers use to slow down traffic on streets to make them safer. See https://en.wikipedia.org/wiki/Traffic_calming
Speed limits in US highways had been introduced in 70s to save gas during the crisis. Let’s all agree it had nothing to do with safety.

The claim that 30% of incidents are caused by speeding are also questionable. Few years back I was rear ended by someone talking on the phone. The officer wrote speeding as the cause of incident. When I asked about it, he replied that the safe speed in this case was zero. Just wander how many of these 30% are the same.

P.S. I rarely actually go above the speed of the traffic flow. I think it is the safest to drive at the same speed as others even if it is above speed limit. On the other hand, drivers in the left lane going 60 mph when everyone else is doing 85 mph are the real danger on the road.

You forgot about pedestrians. Should we throw away research that says pedestrian death is more likely when speed is higher than 50kph?
There are no pedestrians on highways.
Babylonian alert: in some Englishes, "highway" is "road", whereas in others it means "high-speed motor vehicle road". Confusing, yes: given that the article talks about rural and city roads and the GP tries to refute it through freeway speed limits, apparently some of the confusion is present here as well.
Very good point. Also, in some areas highway is the term used in law for any "road", even if it's not in common use and residents still equate highway with a more high-speed limited access facility.
In American English, a highway is, what you term, a "high-speed motor vehicle road". As far as I know, the equivalent term in other English speaking countries (and other countries where English is used as a secondary language) is motorway.
That is not true, even in the US.

For one, people may be allowed to walk even on freeways if their car has broken down and they are walking to the nearest exit. I've walked on the highway because I ran out of gas and it was only a mile to the nearest gas station. I've also picked up someone rolling a flat tire to the next exit.

Here's the relevant Louisiana law, from http://legis.la.gov/Legis/Law.aspx?d=88191 :

> Pedestrians on highways or interstate highways:

> A. Where sidewalks are provided, it shall be unlawful for any pedestrian to walk along and upon an adjacent highway.

> B. Where sidewalks are not provided, any pedestrian walking along and upon a highway shall, when practicable, walk only on the left side of the highway or its shoulder, facing traffic which may approach from the opposite direction.

> C. It shall be unlawful for any pedestrian to cross an interstate highway, except in the case of an emergency

Here's part of the law for Idaho, from https://legislature.idaho.gov/statutesrules/idstat/Title49/T... :

> (3) Where neither a sidewalk nor a shoulder is available, any pedestrian walking along and upon a highway shall walk as near as practicable to an outside edge of the roadway, and, if on a two-way highway, shall walk only on the left side of the highway.

Thus, it can be legal to walk on a highway. Do people do it? Yes.

In New Mexico, people do the pilgrimage to Santuario de Chimayo. Here's a picture of people doing that while walking on the shoulder of Highway 503: https://www.abqjournal.com/562845/route-for-chimayo-holy-wee...

Here are some monks doing a pilgrimage along local and state highways from New Orleans to Memphis. https://www.catholicherald.com/Faith/Dominican_friars_to_mak...

Here's a man walking around the Salton Sea, from http://dineshdesai.info/saltonwalk/index.html :

> "Is it permissible to walk along the new section of the highway south of 66th Avenue? ... a CHP officer picks up the phone and tells me that it is O.K. to walk along the old 86 as well as the new 86S."

It's usually only legal to walk on a highway if you are leaving a broken down vehicle. Even then, it's basically a death wish.

It's not however legal to walk onto a highway, or used a bike, or motorbike under 250cc. It's posted at the on/ramp

I pointed to the laws of two states which seem to say something different than what you just wrote. (Specifically, there is no blanket ban which makes it illegal to walk onto a highway.) I could point to others if that would help.

I pointed to images and accounts of people walking on highways, including a pilgrimage which has been done for 200+ years.

I'm therefore confused about why you write that it's not legal to walk onto a highway, when I gave plenty of evidence that it is both legal and something that people do.

I'm also confused why I was downvoted. What sort of evidence is needed to disprove ronsor's statement "There are no pedestrians on highways."?

I think you are specifically talking about restrictions on a limited access highway. (lsh123 brought up "US highways", which is a broader term). Even then this, there isn't a blanket restriction across the US. For example, concerning bicycles I'll quote from https://en.wikipedia.org/wiki/Non-motorized_access_on_freewa... :

> Different states of the United States have different laws. Cycling on freeways in Arizona may be prohibited only where there is an alternative route judged equal or better for cycling.[1] Wyoming, the least populated state, allows cycling on all freeways. Oregon allows bicycles except on specific urban freeways in Portland and Medford.

I used to live on one of those states which allow bicycles on the interstate, and I've seen people cycling on it.

But you don't have to take my word for it. Here's a WA DOT poster describing how cyclists will need to detour off the interstate due to construction, http://www.wsdot.wa.gov/NR/rdonlyres/F4E32F19-5443-417D-BE5D... , with text like "Westbound bicyclists are required to leave Interstate 90 at Exit 62 - Stampede Pass near milepost 62."

Or from http://www.dot.ca.gov/hq/paffairs/faq/faq67.htm which says "Of the more than 4,000 miles of freeways in California, about 1,000 miles are open to bicyclists."

And yes, even pedestrians can be on interstates. Going again to the pilgrimage at Chimayó in New Mexico, here is news coverage describing people walking on the interstate.

> "Noah Martinez takes a short break Wednesday and changes his socks in anticipation of walking up La Bajada on Interstate 25, continuing his 90-mile pilgrimage ... " - http://www.santafenewmexican.com/news/local_news/faith-tradi... (with picture)

> "As usual, hundreds of pilgrims have already been on the roads – from Interstate 25 to the small highways leading into Chimayó" - https://www.abqjournal.com/987674/pilgrims-progress.html

Why do you believe I am incorrect in my evidence?

> I pointed to the laws of two states which seem to say something different than what you just wrote.

It’s because it’s a federal law, not a state law. See 23 USC 101 if memory serves.

Here's the text for 23 U.S. Code §101: https://www.law.cornell.edu/uscode/text/23/101 . I see nothing concerning pedestrians on highways.

What I do see is an expansive definition of "highway": "(11) The term “highway” includes— (A)a road, street, and parkway; (B)a right-of-way, bridge, railroad-highway crossing, tunnel, drainage structure including public roads on dams, sign, guardrail, and protective structure, in connection with a highway; and (C)a portion of any interstate or international bridge or tunnel and the approaches thereto, the cost of which is assumed by a State transportation department, including such facilities as may be required by the United States Customs and Immigration Services in connection with the operation of an international bridge or tunnel."

Given all the evidence I've given which shows that people do walk on a highway, and that it's legal, I would appreciate a stronger counter-argument than what you made.

Since "highway" includes parkways, here are some people who walked/biked on the Blue Ridge Parkway: http://www.blueridgeoutdoors.com/go-outside/hiking/ten-years... .

And here are people walking the Natchez Trace Parkway: https://natchez-trace.thefuntimesguide.com/road_walking_natc... .

I agree it’s probably safest to follow the flow of traffic, because it’s speed differences and changes that I’ve seen cause the most accidents or near-accidents. When people are slowing down, changing lanes, exiting, or other things that cause speed differences between vehicles, it reduces other drivers’ ability to predict what’s going to happen, introducing more opportunities for a wrong move.

Whereas I’ve done the trip between SF and Reno/Tahoe many times, for example, and depending on time of day (day of week, season of year, &c.) there are parts of I-80 where virtually all the traffic flows smoothly and consistently at 80–85mph. I have a hunch that it’s not a coincidence that I’ve seen far fewer accidents in those areas—all you have to do is stay awake, steer, and hope a deer doesn’t jump out.

As said in an advanced driving class I once took, “speed doesn’t kill, its change in speed that does.”
I've found it much more relaxing to just drive the speed limit, keep to the right as much as possible and to be a courteous driver in general.

I let the traffic flow around me, instead of trying to keep up with everyone. When I'm driving, I relax and try not to stress about getting to my destination as quickly as possible.

YMMV of course, as I'm in Europe and driving habits do differ a lot.

I think inattentiveness and impatience are the biggest killers in traffic. I don't really care if people are going 10 over, as long as they're not harassing other people.

> I've found it much more relaxing to just drive the speed limit, keep to the right as much as possible and to be a courteous driver in general.

On surface streets (streets within city limits where the speed limit ranges from 15 mph to 40 mph), I have the same experience, but on highways/motorways, I don't find it relaxing at all because everyone is passing me at relatively high speed differentials.

In other words, you feel a sort of peer pressure to speed, in order to match speed with those people?
Is it really speeding if one is going the speed of traffic? Traffic speed is largely determined by the design speed of the roadway, not the posted speed limit. Also, going substantially above or below the speed of traffic puts one at an increased risk [1] of being involved in a collision.

[1] https://en.wikipedia.org/wiki/Solomon_curve

Hereabouts, if you drive in the right lane, you'll be stuck behind someone going 5-10 mph slower than the posted limit.

(For what it's worth, it can also happen in the leftmost lane, just not quite as often.)

This is sometimes caused by older people because reflexes detoriate over time. Right lane also has significant amount of merge/exits which also causes slowdown.
And then you overtake those people, when an appropriate gap appears. Or you exercise patience and wait.
Or you could just move one lane to the left...
I believe that the speed limit is based around speed. I think it is generally safe to drive the speed limit, except under extraordinary circumstances. I also think it’s rather easy to drive at less-than-safe speeds (there are grey areas depending on circumstances) while ignoring the limit.

I mean, maybe you could make efficiency arguments, but in my experience going over the speed limit rarely helps you get anywhere faster around major metro areas. So such arguments would probably have to argue for specific circumstances. Even the autobahn has speed limits posted in certain areas.

If we’re going off purely anecdotal evidence, I’ve noticed that people tend to speed because they are poor with time management, or they are paid to speed by some organization (consider pizza delivery).

Meanwhile, what are you proposing?

The article and discussion thread confuse highway speeds with city speeds. On highways, there's a delicate tradeoff between, (a) long travel time and congestion, and (b) safety.

In city, speeds are generally unsafely high, for trivial travel time benefit.

> The claim that 30% of incidents are caused by speeding are also questionable.

The statistics actually say that they're "speeding related", not caused by speeding. Also, they conflate alcohol related crashes with speeding related crashes.

If you exclude alcohol related crashes, and crashes where someone was driving too fast for conditions, it drops to around 5% to 10%. According to the Virginia Crash Facts document from 2015[1], "speed too fast" was cited as a factor in 7.74% of fatal crashes (page 35 of the pdf document). West Virginia [2] has a similar percentage for "exceeding speed limit" (8.24%)

[1] https://www.dmv.virginia.gov/safety/crash_data/crash_facts/c...

[2] https://transportation.wv.gov/highways/traffic/Documents/200...

This is very true, and is a phenomenon that one can observe on 280. Traffic flows with >70mph usually but can come to a sudden stop, which forces experienced drivers to take safe stop at shoulders. Or if you had a brief moment of attention slip, to the rear end of the car in front.

Driving is usually about the flow, and anything that causes change to it (especially sudden ones) are dangerous.

It's a shame that statistics don't back up this hoary old saying. Turns out that modeling drivers as if they were ideal gas particles doesn't give you the numbers you expect.

Meanwhile, lack of respect for traffic laws due to inappropriately-low speed limits arguably does get people killed.

> Meanwhile, lack of respect for traffic laws due to inappropriately-low speed limits arguably does get people killed.

This is one area where I believe we need to treat the "lack of respect" part, i.e. beat the people into submission. Because it's not reasonable to optimize speed limits for what a driver feels should be appropriate - a driver takes into account his own position and situation only, while optimizing traffic is a much larger-scale exercise.

(Also, frankly, it's the speed that kills. If either the pedestrian or you were dumb enough to get into crash at 50km/h, you'd get into an even harder crash at 100km/h. I cringe when I hear drivers wanting to raise speed limits on the roads that have foot traffic crossing it, children playing on the sidewalks, etc.)

German autobahn traffic would like a word with you. Drivers over there are pretty good to find out their reasonable speed. There's a ton of respect between drivers too. Probably the most respectful driving culture I drove at.
Aside from the fact that the parent was talking about city streets, not freeways...

I find Autobahn driving very stressful. Crossing the border into Switzerland, which has a general speed limit, traveling becomes much more enjoyable.

I was talking about his general sentiment that people don’t consider others and have to be beaten into submission.

Out of countries I drive at, Germany is least stressful. Especially because drivers seem to be very considerate of others. Including, if not more, on unlimited autobahn sections.

Haven’t driven in Switzerland yet though.

> I was talking about his general sentiment that people don’t consider others and have to be beaten into submission.

It's not that they don't consider others (though there are plenty of angry drivers out there). It's that they're assuming they know better than traffic engineers and legislators. That assumption is full of hubris, and even if sometimes correct, it makes it more difficult for people setting the limits to do global optimization. But yes, ultimately it is - maybe unintentionally - not considering other users of the road system.

It's that they're assuming they know better than traffic engineers and legislators

I think it's very safe to say I know better than legislators who've never been within hundreds of miles of the road I'm driving on.

It may not be as safe to say I know better than the engineers, but the engineers' opinions are of very little interest to the legislators.

We can't just go changing the laws because some segment of the population doesn't like speed limits.
Real-world driver behavior is exactly what should define the speed limit, if you're interested in safety. Google "85th percentile rule."
If the 85th percentile is faster than what is safe, you need to change the road design so that the 85th percentile goes down, not just raise the speed limit.
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It sounds like you didn't actually do any reading on the subject.
A thoroughly researched article vs an offhand gut-check.
For documentation for said gut-check, do a search on "85th percentile rule."
Inadequate drivers kill, not the speed.
Inadequate drivers go too fast for their own skills.

Adequate drivers know that speed does kill, or at least makes accidents much worse. They are not overconfident fools.

Good drivers know the rules of the road and follow them, they know when to bend them, and when not to bend them.

Speeding isn't worth it, you gain a minute here or there, that's it.

I suppose so, but increased speed increases the likelihood that “inadequate” driving causes an accident, and that that accident will be fatal. And IMO most humans are “inadequate” drivers, in terms of risk of death driving—something like 1 micromort per 250 miles, or 1 in 6000 chance per year for the average driver.
That's like saying "Guns don't kill people, people kill people".

Which is bullshit.

Is it just that americans can't drive? In my country road fatalities are 4/100000 people. This is a country with as many vehicles as persons (so a lot of driving). In the US the fatality rate is apparently 12/100000.
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How many miles do your countrymates drive, on average? Americans drive ~12000miles/year, per car.

Also many americans drive very large cars that may be more dangerous to others.

I think that's it: citizens of the United States are incapable of driving.
> a majority of the severe injury and fatal collisions are preventable, so they are not accidents

They are indeed accidents, using the definition which implies unexpectedness (rather than the definition which implies chance).

It's not just speed it's the distance that you keep. If everyone kept to the 3 seconds rule, which basically applies at any speed we'd all be safer. Further you simply increase that when there's ice and rain.

France has broken white stripes along side their motorway with gaps every 4 seconds travelling at 80 mph. It's beautifully simple and saves on paint too.

One of the most important rule we tend to forget.

Distance and less variance in traffic speed.