Ask HN: Is a phD a good way to focus & motivate you?

39 points by throwaway1 ↗ HN
I'm thinking of undertaking a phD in an area that interests me - part-time, whilst I continue to work.

Apart from the questions I have around time commitment, etc, I would like to know if a phD is a good way to focus and motivate me to complete an original piece of work?

I spend a lot of time starting numerous projects but never getting them to where I want to take them. I think this is mainly down to it being very difficult to motivate myself when I'm 'tinkering'.

In a dream scenario, completion of the research would lead to something, that could be end user ready/commercialised/exploited through some more work.

Any war stories, anyone here taken that approach? Is it flawed? Anything I should watch out for?

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Although I'm not pursuing a PhD nor do I ever plan on pursuing one, my father has one in Theoretical Chemistry from UCLA. He tried to raise venture / angel funding for a desktop computing startup in the early 1980s a few years after he graduated and got his green card, and one of the things that really got in his way was, in fact, his PhD.

The reason is that his potential investors and perhaps investors in general hold an innate bias against those of the academic system, namely that they're impractical eggheads who couldn't possibly know how to run a business.

He removed all refernces to his graduate education from his applications for funding and that actually helped him get more meetings - he eventually got funding from an angel who actually valued my father's PhD but it took a long time to find somebody who didn't dismiss him because of it.

That was 25 years ago - things might be different now that PhDs are more common, but I figured I'd share his experience with you.

In most environments I think there's definitely a bias against PhDs as impractical eggheads. In terms of business, I think most investors will look at PhDs as somebody looking for a large personal research grant rather than somebody looking to start a business -- a reputation I think is often well earned having seen a number of businesses run by PhDs go under simply because they thought the key to the success of the business was more researchy things rather than more customer focused things.
I supervise a couple Ph.D. students working full-time jobs.

It's definitely a challenge for them, and it requires immense self-discipline.

Coincidentally, I just posted this morning about the three qualities of successful Ph.D. students--perseverance, tenacity and cogency:

http://matt.might.net/articles/successful-phd-students/

The middle part of grad school is generally depressing: you're failing constantly, your work is getting rejected everywhere, and you get consumed with self-doubt.

It's tough to get a Ph.D. part-time because to do it right, it must consume you. Exceptions are rare.

Also, if you're hoping that what you have at the end of a Ph.D. will be ready for end users, you might want to consider that the benchmark for software in academia is "proof of concept." Most academic code is a disaster in terms of usability and maintainability.

The code is so awful that I even drafted a special open source license to encourage academics to release it--the CRAPL:

http://matt.might.net/articles/crapl/

Thanks for the link looks useful.

<i>"Also, if you're hoping that what you have at the end of a Ph.D. will be ready for end users..."</i>

I have been writing production code for a living for the last 6 years so that doesn't bother me. If other contribute then yes it's likely it wouldn't be production ready. To be honest I don't expect anything that comes out of a phD to be ready for end users without considerable work with a different focus. I think to even get that far will be a great achievement for me.

The commitment on top of a full time job is my biggest concern. I think I would be taking quite a lot of leave to concentrate on research full time.

I think you might have it a little bit backwards. You need a fair amount of focus and self-motivation to complete a PhD. If you already are having issues with this, starting a PhD would be like giving a crack addict access to a large, cheap supply of crack.

A lot of it will also depend on your advisor. A more hands-off advisor will certainly mean trouble for you, as the required pressure to keep you focused will not be there. Finally, conference deadlines are the other big motivator for PhD students. If you don't think that would help focus you, then you'll be setting yourself up for failure (and possibly depression).

Also, I'm not sure how feasible it is to do a "part-time" PhD. That might work with a master's where it's almost exactly like bachelor's part 2, but a PhD is more of an all-or-nothing endeavor. The one exception I know of is for people starting/spinning-off companies based on their research. Even there, it's a lot of work, and I personally find it very hard to maintain good forward progress in both at the same time.

My focus and motivation is something that I think about a lot. At work I am very focused and motivated. My work is project based and deadline oriented, and so I have no trouble focusing in that environment. My colleagues, and the fact that I work on "real" problems motivates me. I just can't transfer that easily to when I code in my spare time - crucially - on something that I see through to completion.

for example one of my side projects is a webapp I have been building since september 2009, at which time I worked on it very intensely. Then I left it for a good few months, to only pick it up again when I was reminded that the problem it would solve was still a very real one - this spurred me on to work on it for another three months or so. I haven't picked it up again in the last two months.

I think I need real people around me to make the problem appear much more real, and keep me motivated. I think that is my rationale for this approach.

I think I need real people around me to make the problem appear much more real, and keep me motivated.

What about users/customers? Perfectionism aside, how about launching a version 0.1 of your webapp?

>> My colleagues, and the fact that I work on "real" problems motivates me

Unfortunately, both of these are hard to come by when working on a PhD. They are actually the two areas that I struggle with most in my PhD research. Getting a PhD is very isolating -- you are often the only one working on your problem, and it often seems like no one else cares. Also, I enjoy more real-world, applicable problems, yet most of what PhD students work on is theoretical or not market-ready by far.

Parent post needs to be upvoted a lot more.

I have a friend who has a PhD, and I regularly joke with him about being the "world's leading expert in something 10 people in the entire world give a shit about." Unfortunately, the joke is only funny because it's literally true.

It sounds to me like you need a co-founder, not a PhD.

I've worked from home on my own projects off and on for nearly 20 years and still have some of the problems you describe. Go and do a project on a customer site and they cannot believe how efficient I am. Started a (failed) project with someone, the pressure of having someone else relying on me was great (not that it is the reason it failed, but he didn't quite feel the same way).

Do something at home and hey I'm replying to this on HN :-)

Find someone to team up with and do what you really want to do, don't try and distract yourself with something else you may never finish.

If you have to ask yourself whether you want to do a PhD, the answer is no.
Can I ask why it is an outright 'no'? Is it not ok to ponder on something of this magnitude before diving in?
I think jerf means that for the vast majority of PhD students, the most motivation you're going to have is at the beginning. It only gets worse from there. So if you have serious doubts before diving in, you're almost certainly going to have real trouble during the PhD.
Exactly; I meant that if you're not 100% sure already, you should probably stop.

In fact even being 100% sure itself probably isn't enough, but I for one will at least stop second-guessing you, since being able to perfectly predict who will succeed in advance is basically impossible.

This is a big life decision and it's exactly the wrong time to be a romantic about it. Trying and failing for a PhD is hugely expensive in opportunity cost. Trying, succeeding, and depending on a faculty post on the other end to make it all worthwhile can be pretty dangerous, too.

A lot of us in the 15-35 age range have been force-fed the idea growing up that encouragement is automatically good, regardless, and the entrepreneur community can be especially prone to this because you need a lot of drive to be an entrepreneur. I actually think that's ok for entrepreneurship, because the worst case isn't really all that bad unless you are really stupid. (Incorporate early, incorporate often; don't take on debt personally.) You at least get some very valuable experience. That's not true for everything. Getting your PhD is one of those things; a partial PhD is not worth it. I would be appalled if I encouraged someone to get their PhD and turned out to be that little tipping factor, only for them to find two years in that they are miserable and can't finish. If anything, a little light discouragement is what is really called for; if that's enough to turn you away from a PhD, then good! You were in trouble anyhow.

Life advice is serious business and unthinkingly spouting "common sense" can be very destructive.

But typing all this out is certainly less... pithy.

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A little simplistic I think. Big decisions should include the head and not just the gut.
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You absolutely must choose the right supervisor, at the right university, to match your attitude and lifestyle.

I just can't emphasise this enough. If you're naturally scatty and unfocused, you need a supervisor who can rein you in and give you some direction; if you tend towards hyperfocusing, you need a supervisor who can broaden your interests and allow you to make connections you would have missed.

Maybe I haven't expressed my self properly - I apologise, I wouldn't by any stretch of the imagination describe myself as scatty or unfocused. The question for me is, will I be focused enough, bearing in mind how big an undertaking this is.

I am hearing from a lot of people (not just on here), that having the right supervisor is essential. I will make sure to ask him just as many questions as he will me when I see him tomorrow. Thanks Tom.

If your objective is only to get focused and motivated, and not necessarily do research, a PhD might be too much of a time sink (I am a PhD student in CS). More so if you are thinking of taking it up part time, since most of your free time will be spent on it. Further, expect that the first couple years will not give you many positive returns to motivate you to go on: those are mainly spent building the foundation.

Having said that, if you truly enjoy the process of research, that might be just the thing to get you more focused and motivated. I definitely enjoy it at the moment.

In summary, don't go for it only to get motivated - if it doesn't interest you, it might end up taking too much energy for nothing.

I enjoying learning and discovering new things. My main motivation is to produce an original piece of work - something that will define me, if you will. A magnus opus.

Is it a waste of time that after two years of part-time research you find that the phD is not the approach for you and you abandon it?

The finding it interesting bit, is another questions in the back of my mind. Will this be something I will find interesting enough to keep me going for the next few years.

"My main motivation is to produce an original piece of work"

In that case, I suggest working on it right now, before a PhD. You can start doing a heavy literature review on a focused topic, and try to improve the state of the art by however small you can. The standards for publication are much lower than what many people outside academia believe.

You can do this and even get a publication without an advisor (may be not at a premier venue but a decent one nonetheless). That gives a great sense of accomplishment.

If you want to continue, the work will surely help you in your PhD (won't be wasted time). If you don't like it, you can move on to other things (and it won't feel like giving up on a long commitment).

The reason I say this: the beginning of a PhD is probably the hardest time to see results, and keep you motivated. So starting small would be helpful. Once you believe you need larger goals and are not satisfied by the small accomplishments, you can go for the long haul!

I'm sorry, I just LOLed the moment I read this headline.

I'm a PhD student hopefully 6 months away from finishing.

PhDs are like running a full marathon. You don't do it because you want to stay fit; or because you enjoy running -- marathons wear you out, cause injuries, and eventually are far worse for you than regular running. You only do it because

1) you want to learn how to run marathon-sized lengths (i.e. you want to be capable of wrapping your head around a multi year unbounded problem)

2) you want to have a sense of accomplishment

It seems you do want to use this as a way of learning structured thinking. But remember that:

1) Your life is going to be fucking depressing as hell.

2) It's many years of not knowing what the hell you're doing.

3) You're giving up your youth for a shot at something completely unquantifiable.

Bottomline: If your job doesn't require it, stay the hell away from it.

I agree: A PhD is too painful to complete one for non-work reasons. I defended 12 months ago, but I really like teaching at the college level, so I stuck it out. If you don't need one, you almost certainly don't want one. They don't teach you how to focus, they instead get rid of the people who can't. It's a winnowing process at least as much as it is a learning process.
I think I was 6 months from finishing for several years.
Most good PhD programs won't take part-time students. It's all or nothing.
Getting a PhD in Computer Science is premature optimization.
i've worked on code written during a phd that eventually graduated to a product. my role was making it production ready.

code written during research is a complete mess, and necessarily so: you don't know what you're going to end up with. you try this, you try that, you hack it, you tweak it six different ways. often things only work in a few very specific situations; generalising to more useful situations can be difficult.

a phd won't motivate you. the right environment will educate you on the latest techniques though and teach you to be critical of them and improve them.

you'll also learn how to write code quickly---i find deadlines in academia more intense than my industrial experience (perhaps because the outcomes are far less predictable).

i wouldn't do a phd part-time:

1. it's intense.

2. you want it to be over as soon as possible.

Some really good comments here. Most seem to advise me to stay the hell away. I will be pondering over this long and hard over the next few weeks/months and doing a bit more research before I take any action.
I left a career to do a PhD at age 42. It definitely helped me take on challenges that require much more technical knowledge than if I had stayed on the "tinkering" path.

The distilled version of my lessons learned: 0) Hard to do a PhD part-time. Consider "retiring" for a while.

1) Your advisor will be focused on cranking out publications to advance their career. Not always the same as increasing the amount of knowledge in the world. You might be viewed as free labor in this effort. Protect yourself.

2) Your advisor will not help you manage your time or set goals. In fact they might need help in this area themselves.

3) If you haven't been in school lately, or deep into work related to your topic, expect to spend a lot of time "getting the rust out". Painful but useful.

4) The younger brain can solve problems more quickly, the older brain can pick better problems to solve. Your advisors won't know this either.

5) A storied career in academia is unlikely for an older student. (See Robin Milner for a great exception.) Keep your business network alive and growing the entire time you are in school.

6) The #1 goal is to finish. OK to repeat that to yourself over and over. Your thesis need not be the last word on a topic to be acceptable or even good.

7) You will feel like an idiot every day until you suddenly realize nobody can answer your questions anymore. That day you should start writing the answers in your thesis and finish it asap.

Finally, other than all the pain and anguish, it is an invigorating experience to find the brain still working.

Some great tips here. I am 30 this month, having been working in industry for the last 6 years. If I were to take this on and were to make good progress, I would consider "retiring" for a year or so to finish things off.

The point you make in 1) and 2) echoes a lot with what others are saying about finding the right adviser. I will certainly pay a lot of attention to this.

Oh, you're still a youngster :-). Married? Spouse gets at vote.

I minimized risk by having three advisors, whom I ended up relying on for different purposes. This was unusual in my school, but I found it worked well for me. One had a lot of experience and was great at dealing with paperwork and people problems. One turned out to be absolutely brilliant at idea generation and horrible at everything else. One was great for brainstorming and working on proofs. Neither of the latter two were what you might call "transactional" when it came to meetings and goals.

At the end of the process, it was my fellow students who who actually read my thesis and provided edits and suggestions. All for chocolate and cappuccino.

I am married. Would it be insane if I just became a father for the first time a few weeks ago?! I wouldn't be looking to formally start something until early next year though.

EDIT: Forgot to mention that my spouse would have a big say in this too.

Nah. A kid will keep you sane. Best cure for a bad day ever invented. Also, kids don't get cheaper as they age. Might as well get the task done quickly.

Just make sure spouse is truly on board. Your stress is their stress and vice versa. I might add that my wife ended up getting a graduate degree and a new career, and the experience brought the whole family (3 kids) closer.

Re: age. This is a big deal. Younger (<30) have a large advantage, particularly with respect to the amount of free time you have available. Don't start a family during school. It's certainly possible, but slows you down, which is the major killer of graduating. If you're >50, your odds of a full-time teaching appointment are not good.
This sounds harsh, but I'd rather be honest and risk that.

I have a PhD in physics and work supervising doctoral students and early stage post docs.

A PhD will not help you personally unless:

a) You want to prove to yourself that you can do something original AND

b) You are incredibly fascinated by a certain field, to the point of obsession AND

c) You are capable of continuing to work, unaided and unsupervised for up to 6 months (or longer!) at a time with no encouragement and no external pressure.

I don't know what CompSci is like, but I cannot imagine that it is so different to physics or mathematics, which is where I have some experience.

I wouldn't recommend doing one, if those given above honestly are your reasons. Seems like you should take a part-time job working for a small startup (commercial) or join a well-run open source project (not-so-commercial).

Otherwise, look at ways of motivating yourself using external tools. Set deadlines, make lists and allow yourself rewards for ticking off items on your list or hitting those deadlines.

If you do start a PhD, it sounds to me like you risk giving up half way through, having wasted 3-4 years of your own free time.

Wow another overwhelming "no don't do it"! From someone who's been there and done it.

So, genuine questions: why did you do it? and what were your reasons? And finally if you could go back in time, would you decide to do it again?

I did it because I had a degree aged 20, and my options were a PhD including international travel, freedom and the chance to stay (nominally) at Uni - or take a general management job or jump into a consultancy. I lacked imagination ;-)

If I could go back in time, I would...hah! So I just sat here for 5 minutes. I honestly don't know. I jumped in head-first and gave up everything at home for my PhD. Doing my PhD allowed me to live in three different countries, meet a whole load of new people, live through some intense experiences (30 hour 'days', travelling and working through 8 countries in 8 days, become an expert in subject X and give a presentation on it to world experts in 3 days etc. ;-) and grow up. I learned a lot about myself. The physics and computing and mathematics were incidental, almost. But I gave up a huge opportunity cost in going into finance or starting a company. But who knows what I would have amounted to, otherwise?

From what you're saying, none of those experiences would apply to you. You're not used to living on $15k per year, and would be working a day job along side the studies. Since you'd hold onto your regular life, you wouldn't travel for renumeration amounting to just under the cost of living and you're probably too experienced to tolerate the amount of crap a grad student gets on a daily basis.

I'm not negative about doing a PhD, I think. I'd recommend it to you heartily if you were in your early twenties and wanted to go do something unique, exciting and demanding. But from your post, you're not talking about going all-in. You're talking about doing it as a hobby, almost - a help to what you really want to do. It doesn't (or shouldn't) work like that. My advice would be to do what you really want to do, and not worry about getting an external boost or credit - which is what a qualification is about, I guess.

In fact, from what you've written, it sounds to me like you don't enjoy getting your own projects done because you are busy achieving stuff during the day. I don't think that anyone can be focused and productive 15 hours a day. Try changing jobs, taking a less intense day job to concentrate at home or finding some way to roll your own projects into your day job properly.

A word of caution: I don't know anyone who did a PhD part-time. My advice is worth what you paid for it ;-) You may get lucky and have an awesome advisor who cares about your topic. You might have some incredible idea that needs academic help to bring to fruition. If you know exactly what you want to do and can find an advisor who is as enthusiastic as you, go for it! But from your post, I guess that's not the case.

Re: part-time. I was able to finish part-time, but did a ton of work full-time for the first couple of years. My research suffered, but because my job linked with the research, it worked out well.

One thing that's not well known is how much you'll be working while in school on grant-funded projects. You'll be working no matter what, it's just a matter of getting a good one to work on.

Your first paragraph alone is a great advertisement for a phD! But you are right in what you say in the third paragraph. The qualification is the last reason why I want to do it.

I do see it as a potential way to transition into a different lifestyle - a startup maybe? But I guess I haven't got the guts to go all in at this stage and risk so much (a disadvantage I have), and I see this as a safer way of entering that arena. If (and most likely) it doesn't get that far I guess I will have 'accomplished' a body of work.

Oh and my brother has completed a phD part-time in the biomedical sciences. I will consult him on his views too.

Well made points and they make sense.

Perhaps, if the OP does not already have one, a Master's Program is a good way to start? Is does not require a dissertation and many have a non-thesis option if you do not want to do original research.

Of course, you do need a fair degree of motivation to finish even a masters, but it is a much lower bar than a PHD. While your direct advisor may or may not pay you much attention, most masters programs are centered around a series of classes that are like a harder extension of your undergrad education.

Also, if you are doing this for career purposes, a masters is a "sweet spot" in terms of return on investment in education. It is much less costly than a PHD, and does not run the risk of intimidating potential employeers in the way that a PHD might. But at the same time, it sets you apart from people holding only a bachelors.

(For full disclosure: I am currently in a masters of math program while working full time.)

I agree that doing a master's is the best financial investment right now and can be a good way of learning something a bit more detailed and focused than undergrad. But I think that even a master's won't achieve what the OP wants.

(S?)He seems to be looking for motivation and a cheer-leader for his own projects. The best way to get that is not in academia.

I already hold a masters.

I would not be doing this for career advancement, and it would not be something that is the opening gambit on my CV either as there are far more relevant points to be made.

I AM looking to do original research, and - he says romantically - it would be nice to do something that directly contributes to society on top of this.

> join a well-run open source project (not-so-commercial).

This sounds like the best advice here that answers the question.

My two cents (take with salt, as I'm a math Phd student, not CS):

A grad program absolutely CAN motivate you, IF you are motivated by failure and feelings of inadequacy. In math there is a real divide between being book smart and being able to do research (to put it mildly, it's more like a chasm). Most students have been validated their whole lives by being better than the rest, and finally coming to an obstacle that doesn't yield can be life changing.

For me, my self identity was absolutely tied up in proving myself as a mathematician, and my first few years of research were HELL. Total self sacrifice, total commitment. I came out the other side of the blaze a new person, and better for it, I think. I've lost the desire to do math, but I've gained the self confidence and mental integrity to disappear into a cave for years to work on a project with no sense of validation from others.

There were other motivating factors: wanting to compete with other students, wanting to impress my advisor, etc. NONE of those motivations survived the pain of research. And, to be honest, now that I've proven myself, not even that desire exists anymore. As of now, I can't fathom doing a PhD again. The only thing that can motivate me now is working on a really interesting problem, and to be honest academia ISN'T necessarily the place for this. At least in math, there really isn't that much freedom in what you can research.

If you can find a good research project that involves enough people to keep you motivated from social pressure, I say go for it, as it sounds like you're really jonesing for interesting work and simply need the motivational factor. Otherwise, if you can find some other way to stay motivated, I'd say do research on your own.

(As a side note, I have a Mech Eng friend that just got his PhD. He released much of his research as an open source library which apparently has attracted a pretty substantial user/contributor group. So it is possible to write quality code in an academic setting, especially if you've already have commercial experience and a desire to hold yourself to that level. Most academics have simply never been in a position where they Needed to write commercial quality code).

I think your approach to motivation is flawed. You're throwing yourself into a situation where you require an external motivator in order to get things done. Even if that works, you still haven't fixed the root problem, that you lack the internal motivation to pursue your goals. The best you can do under this system is to jump from one external motivator to the other.

To develop internal motivation, force yourself to work on your projects a little bit each day. You're not going to go from zero hours to five hours a day in the space of a week. Internal motivation is like a muscle you have to develop over long periods of time. Resign yourself to the fact that you don't have the discipline to live up to your expectations right now, but eventually you will if you push yourself a tiny bit more each day. As Epictetus once said, nothing great is produced suddenly.

To actually answer your question, no you shouldn't go for a PhD, since it's not an external motivator, it's an anti-motivator. When I started my doctorate I wanted nothing more than to be in graduate school doing research. I would have been satisfied to spend the rest of my life being a graduate student, if only I could continue my work. By the time I finished I was drinking three nights a week, and wanted nothing more than a chance to go back in time and convince myself not to go to graduate school.

Check this older thread also for some perspective and useful advice: http://news.ycombinator.com/item?id=348774
Summary: do it if you want to become a career researcher, but if you want to do creative hacking than cut out the middleman and just do it. Gradschool is the hotbed of timewaste and procrastination so don't do it to get yourself focused. If anything, taking some undergrad courses in some topic that is new to you could be much more useful that way.

Even if you want to get into research, leave all ideals and preconceived notions behind. As others have said, doing a phd is depressing as hell. You will have smart people to hang out with every day, but especially if you are thinking of real world applicability of things, you might have a hard time connecting with most of them.

I just finished up a PhD in Information Systems & Technology, which is related to CS, but much more user-land/application-land oriented. Be careful which type of program you apply to, if you go CS, it takes a lot of math. Look to see if the degree department is part of a business school.

Your real focus is the dissertation; the rest of the courses essentially act as a MA/MS. Make sure your dissertation is marketable (biological stuff is probably the best bet to be hot in 5 years, security and games are hot now, but I'm not sure how much longer).

However, I'd really recommend against a PhD unless it (a) directly helps you in in a major way in your existing career, or (b) you want to become an academic. The latter is a tough field to make it in; go to a high-level university or don't bother. You'd better like submitting grants as well, and relocating is pretty much a requirement. I've enjoyed it, but it's incredibly stressful.

It sounds like the OP is asking "is a PhD a good way for me to actually accomplish something in my hobby area?" In which case the answer is no.

A PhD is a way to obsess about a highly particular part of some field to the point that you can finally gain entry to academia where you can continue to obsess about particulars while balancing teaching students for the rest of your career.

If that's what you want, more power to you, the world is a better one because of people like that, but that doesn't sounds like where you want to go.

I recently finished my PhD in pure mathematics. I'm not currently using it because I made an abrupt and idiotic career switch into something I didn't completely understand, but that's another story.

Your level of focus and motivation is going to be dependent on whether or not you love what you study. Earning my PhD required plenty of long hours with boring problems, boring subjects, and awfully boring theorems. It was emotionally challenging to push around a pencil on problems I hated. It frequently seemed like a complete waste of time, life, effort, etc..

It required a level of focus and dedication that was only possible because I love my subject in the sort of way that keeps me up all night and ignites me with Christmas-Eve-Santa-is-Coming excitement in the morning.

Sometimes it's easy to forget why you love your subject. Sometimes I despised mathematics. Earning a PhD helped me to move beyond these times, concentrate my effort, and make effective project management decisions. These experiences taught me a repeatable process for quickly mastering anything: Concentrate on the elementary, challenge everything, do the grunt work (yes, even when it sucks), and never stop thinking.

Here is the best that I can offer you. I've been considering earning another PhD, but I cannot see the point. Earning my first PhD taught me how to master something. I can now do that on my own.

From what I've heard, the politics are an order of magnitude worse than in the average corporate environment.
I'm almost finished with a PhD in CS which I started after many years of working in industry. Like you, my topic is in an area that interests me immensely. My experiences:

Tried to do it part-time many years ago, gave up after five years. Too difficult to juggle work pressures and research efforts. YMMV

This time around, doing it full-time. Thanks to GFC my savings have dwindled faster than budgeted for. The wife is not impressed and counting down the days to when I submit the thesis. At least, should avoid the "all but dissertation" syndrome.

Research is not tinkering. It is very deep, meticulous, frustrating and depending on your university you will be distracted by having to publish conference and journal papers.

If commercialization is a major goal for you, then perhaps you should be looking at doing a startup.

Consider that having a PhD may actually make you less employable, unless you want to compete for the few jobs in academia and research labs.

If the many comments on HN to your question haven't discouraged you yet, then may I suggest:

* You research in detail the topic you want to do research on. Google Scholar is very good.

* You track down a couple of recent PhD theses in related areas and read them carefully. Ask yourself whether you can match or exceed those standards.

* Write up a research proposal (you'll need it anyway) and only submit it to the top universities.

* If you get accepted, then seek out how you can earn enough to support yourself and family and study full-time.