I think this a great point. If you're in the habit of writing a TLDR for articles, maybe you can try writing the TLDR and then afterwards removing the 4 letters "TLDR" and leaving the sentence there. It's great to summarize in the first sentence.
But how does the reader know you are one of the authors that summarise succinctly at the beginning of every article? Especially as they reader may read many articles of differing quality a day. tl;dr to me, is like statically typed English, it improves readability if you know to look for it.
Yup, composition on the Internet is different from composition for print in which "good writing" used to mean 1) intro, 2) body, 3) conclusion. Now it means: "get to teh point!!!" and maybe, if you have time, elaborate so people can follow your train of thought. When people are used to affording only 140 characters of attention, you wind up skipping all the formalities. TL;DR is a sigil. Sometimes people put it at the bottom (jerks), but at least it's easy to spot.
I know I saw it on the SA forums, where it may have originated. People would reply "too long; didn't read" to dismiss a post, which eventually was abbreviated to just "tl;dr". Anticipating this reply, authors of long posts would end their post with a "tl;dr" summary.
It's the same basic principle as newspaper articles, or the essay format you were taught in school: summary first, details later. Or make your points up front, then prove them.
That only solves a part of the problem, though. Highly upvoted long comments on Reddit are particularly frustrating because so many of them have content that's weak or just plain wrong. I'm convinced that only a small fraction of voters actually read them.
There is also a strong bias toward upvoting more visible content. Higher-voted comments appear first on the page, getting more exposure. For that reason I’ve made it a habit to read comments in bottom-to-top order, in order to artificially make my votes more fair.
Great point, although tl;dr works for short comments, whereas the "trick" of putting the summary in the beginning of a text needs some actual "body" before it works - otherwise it is just confusing.
I disagree. While something that is well written shouldn't need a tldr, it does service as a device for people who consume a lot of text. Its a standard shorthand indicating the author did in fact write a summary
Agreed. Plus, people are trained to ignore "wall of text" but will indeed read text labeled as tldr. It's communicating a summary. Due to the mixed bag of good writing on the Internet, we as readers cannot rely on the first sentence being an all encompassing summarization of the points.
TLDR is just a warning to the reader that the rest of the text might not be worth his time. It also helps to make explicit that the paragraph following it is a summary of the post.
The US military frequently uses the abbreviation "BLUF" (Bottom Line Up Front) for the same purpose as TLDR at the beginning of an email. It's not like the idea of tldr is some perversion born of the Internet.
One of my favorite pieces on writing is "Effective Writing for Army Leaders," available at http://www.au.af.mil/au/awc/awcgate/army/p600_67.pdf . They have hilarious side-by-side comparisons of poor and good writing, such as pg. 13 and 14 (pg. 7 and 8 by page number). I found this during a brevity kick I had after reading David Sirlin's "Writing Well."
That's pretty awesome! Although I think the elements of the "poor" example that draw attention to some potentially pertinent information shouldn't have been removed. (For example, the fact that the applicant is not mission-essential during a training cycle, and that given he has not previous cold-weather injuries, he may be less susceptible to them.)
I don't think this is generally true. The purpose of long form writing is to make the reader draw a conclusion that they may not agree with at the beginning of the article. Studies have shown that once we form a conclusion, we're much less likely to change our minds, so if an article lead with a controversial point we'd internally say "no!" and stick to it rather than letting the article make its point. By not knowing exactly what an article is arguing, we're more receptive to things that could go against our intuition.
I do agree that TL;DRs can be elided for articles that simply state facts or uncontroversial ideas.
That's both a very narrow, unhealthy view of writing and a pretty fatalistic attitude towards your readers. I don't like TL;DR any more than the author of the article, but I don't think having an abstract or brief synopsis decreases the likelihood of you "winning" the essay—or if it did, that this alone would constitute a good reason not to use them.
I think you misunderstood my comment. I wasn't speaking just about having a TL;DR or not but instead more about the difference between long essays and short passages.
Characterizing my opinion of writing as either something you 'win' or 'lose' is itself narrow (and frankly, almost insulting). I have to feel that you coming off this way is a byproduct of the Internet. I'm not trying to chastise you here. I understand that what I wrote initially might come off in a way I didn't intend, but you have to meet me halfway by assuming I'm not a total jerk.
Writing isn't about winning or losing, it's about sharing ideas. And yes, there are better ways and worse ways to share ideas. A conversation around a dinner table is probably better than an essay ever will be - but you can still try to get there. You can either hear this fact and say "aha, I should try to be more clear in sharing my ideas" or you can say "that's fatalistic, and writing isn't a game." I can't fault you for choosing the latter, but I do ask that when I choose the former you remember that I do it just because I want to be understood.
Please accept my apologies. Lately it has felt like everyone around here is trying to win. I should not have assumed you were and I seem to have fixated on the wrong elements of your comment.
Agreed. Aside from assisting in removing bias from the reader, working your way through to the conclusion allows it to remain a mystery to the reader, allowing them to enjoy being walked through the process of discovery, rather than just giving them an answer, then doing a "here's how we got there", which (in some cases) becomes less interesting once the answer is known.
To respond to Fusiongyro's point that this is a narrow view I point out that generally in writing style should change with context. In some cases the author of the article is exactly right about summing things up in the first sentence, in others johnfn is.
TLDR: Whether to use tldr depends on what experience you're looking to give your readers, what you're writing about, and who you're writing for.
You and the GP are actually in agreement with the thesis of TFA (though not the specific argument it's making). TL;DR is unnecessary for two reasons:
1. If you're writing a piece in which "the journey" isn't important, then you should put your conclusions up front like a good journalist.
2. If you're writing a considered, long-form piece in which readers' appreciation of your conclusions is path dependent then a TL;DR is obviously counterproductive - if it's necnessary for a reader to actually read the piece, it doesn't make sense to reward those who skip to the end or didn't comprehend what they read.
TFA took point 1, you and GP took point 2. Nobody (except Charlesmigli) has given an argument that TL;DRs have a place.
I see the tl;dr as a failover to the full story. Those who have time you walk through the journey of discovery. Those who don't you'd rather they could at least see a summary of your conclusion than leave with nothing.
I like TLDR for being able to cmd+F to it quickly. In a well written article with an abstract or a good first sentence, I still have to find the first sentence. With a TLDR, I can jump to that section quickly. I know this sounds like the height of being lazy, but I assure you, it's not.
TLDR is a pragmatic device; it's a written discourse marker. Calling it "unnecessary" is just like saying that "well...", "y'know", "so...", "like" and all those other little "filler words" that your high school English teacher doesn't like are "unnecessary". In formal prose, where all that's supposed to matter is textual semantics, sure, they're not necessary, and I wouldn't use them there. But in informal discourse, they're essential; not for conveying propositional information, but for negotiating social discourse information.
The "TLDR" is all-caps, so it grabs your eye out of the wall-o-text that you may be skimming over, and says "hey here is my basic point". And maybe then you'll go "hey that's an interesting point" and scroll back up and read their lengthy argument, story, or whatever, in all its labrynthine discoursiveness.
And now to demonstrate it I will include some lorem ipsum. Hipster Ipsum, to be precise. Swag polaroid tempor iphone echo park ethnic 8-bit, cosby sweater beard semiotics in. Magna organic neutra, exercitation laborum quis jean shorts aliqua ex eiusmod gluten-free pitchfork butcher. Cosby sweater disrupt keytar qui, beard pariatur lo-fi sustainable magna skateboard sint farm-to-table umami. Intelligentsia pour-over flexitarian, banh mi meh ad meggings thundercats ex. Labore tofu aliquip officia kale chips, bushwick single-origin coffee. Quinoa laborum velit 3 wolf moon placeat eiusmod, nisi brooklyn cred VHS stumptown. Gastropub try-hard intelligentsia, fashion axe 3 wolf moon wes anderson actually officia proident laboris american apparel do.
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Craft beer vero cosby sweater kale chips ex nihil cardigan, truffaut authentic photo booth sed. Irony ethnic keytar post-ironic, ugh enim tonx truffaut before they sold out. Kale chips tattooed terry richardson keytar marfa carles artisan, sunt flexitarian vice ex. Umami sapiente direct trade etsy ut, hoodie readymade jean shorts brooklyn VHS cray polaroid. Anim pork belly swag minim. Master cleanse narwhal cred pinterest. You probably haven't heard of them wes anderson est, high life truffaut culpa stumptown ethical williamsburg vero sapiente.
Etsy plaid irony, brooklyn post-ironic williamsburg dolor butcher master cleanse pariatur aliqua next level cred. Seitan aliquip qui disrupt lomo literally. Sapiente tumblr laborum, gastropub bicycle rights non post-ironic pug ut. Do nisi narwhal, ad odio before they sold out disrupt brunch tumblr polaroid dolore +1 odd future. Viral officia readymade, plaid forage assumenda post-ironic cupidatat you probably haven't heard of them portland sint qui. Cardigan try-hard portland id selfies four loko, assumenda ethical letterpress aesthetic. Neutra non art party locavore aesthetic, actually freegan tonx cardigan godard ex gentrify.
TL;DR: One sentence with a block of all-caps beginning it sure catches your eye at the end of a long post.
Interesting tangent, as someone who was fluent in Latin many moons ago (could speak it at an English conversational pace), I literally had to force myself to ignore your filler (which includes several Latin fragments).
It's from a "Hipster Ipsum" generator. Designers traditionally use a piece of malformed Latin to indicate "there is some text here" without having actual text.
That was completely unnerving. Without even realising I had done it I completely skipped over the block of text to the TL;DR and only after did I realise it was just Lorem Ipsum nonsense.
I totally agree with TL;DR usage, it's a modern device for modern internet communication. People continue to use it because it's useful and works, not because they have an agenda to ruin the english language or are semi-illiterate. Possibly my favourite thing about it though is its lack of pronounceability. Its entirely invented and used as a written construct and is actually quite cumbersome to try to say out loud.
What if TL;DR is not in all-caps, e.g. tl;dr? The lowercase version is quite prevalent on Reddit. Of course it still stands out from a block of standard English prose because of the odd shape of the combination (especially the semicolon in the middle), but not so much as the all-caps version.
It means "too long; don't read." I'm not sure why the past tense variation sticks; but it's a label/post-it/card/sign/placard/billboard/sign-post/warning/caute!/message not to read the identified text for concern of irrelevance.
It's like a voting system. The ";" functions as the hash tag: "#tldnr", "#tldr", etc.
Doesn't make sense. "N" does not pick out the beginning of any word. If you chance across the tag, your interpretation is less obvious than,
"... Too Long; Do Not Read"
The contraction makes sense, and thus the natural transformation into a meta-informative suggestion makes sense. Contractions serve to convey information, usually engendering more intimate dialogue. So it also invites the question of "why not"? And we all know how that goes. It invites the author and really any reader to a game not dissimilar to trolling, usually. It may not take a position necessarily, in terms of the message, and this is not required of what I am saying; however, an explanation of why one would post it at all stands in order. I think the conveying of information to other readers is also important.
I find this a pretty weak argument against the tl;dr. "tl;dr" has become a noun, that means one-line / extremely short summary. Language sometimes grows like that.
A better argument against the tl;dr would be that the piece you're writing it for becomes redundant, provided it's an accurate tl;dr. The term tl;dr wouldn't be needed then, because the tl;dr itself becomes your piece.
If it isn't an accurate tl;dr, there's no reason for providing it in the first place, except maybe for giving a rough idea of what your piece is about. OP rightly points out, though, that conventions already exist for just that. A descriptive title or an introduction clearly distinguishable from the rest of your piece, for example.
Yes, tl;dr (too long; didn't read) was originally used on the somethingawful forums as a dismissive reply to a long wall of text post. Eventually, an OP would preemptively include a TL;DR line in a post to give a warning/summary.
From a UI/UX perspective: "TL;DR" improves scannability.
As a reader, prefacing that first line/paragraph with "TL;DR" means that all I'll have to read is just that part. This is useful because not everyone uses their first paragraph or sentence to outline the general idea of the article. For example, there might be an anecdote, or a quote, or whatever else to start the article.
It's pretty poor UI/UX compared to what we used to use: long subtitles and abstracts set out in separate fonts at the beginning of documents. It's an improvement on a wall of text, but it's not an improvement on traditional writing styles so much as an improvement on slightly older internet writing styles.
If you really need a TL;DR, you failed to fulfill your promise to the reader. Writing should be concise, accurate, and to the point, and we as writers should always strive live by the wisdom of Strunk: "Use less words."
When someone opens your webpage, they are entering into an implied agreement with you. They are seeking information and you are supplying it to them. If they are unwilling to uphold their end of the bargain by demanding a TL;DR from me without giving me the chance to read my words, I don't feel any obligation to satisfy them.
The other half of this implied bargain is that I simply offer what they came to find, and if I fail them in that regard, then I should be required to post a TL;DR because all 2000 to 3000 words I blathered out should be in 50 words or less. If I was able to offer a 50-word summary, then I would have simply tacked on an extra 25 words and eschewed the TL;DR.
If you don't like my attitude, that is fine. You probably aren't my target audience, and this is fine. The World Wide Web is a very large place.
> Writing should be concise, accurate, and to the point, and we as writers should always strive live by the wisdom of Strunk: "Use less words."
I think the feeling is often "I made this so long because I did not have time to make it shorter."
Of course on the web, this is short-sighted and self-defeating. If you have a valuable thought that you commit to the web, you do so in the hopes that it will be read many, many times. You only have to write it once.
So to agree with dizzystar, respect your (potential) readers and spend a little more time making that thought concise.
It is short-sighted and self-defeating because there is nothing written in stone that says that your content is immutable.
I love it when I receive emails from readers asking me to clarify some point, or telling me about spelling errors. I also get requests to remove paragraphs. After about 5 minutes of pondering it, I find that they are usually right. It's not that difficult to delete a paragraph.
'A reader of "The Elements of Style" once sent E. B. White a clipping of a book review that misquoted William Strunk as having advised writers to "Use less words!" White wrote back: "I often wish Strunk could come alive so that I might hear the gnashing of his teeth."'
As a cofounder of http://tldr.io I'd say that having a tl;dr separated from the main article is very useful for readability. Like ps for example it helps structure the text. tl;dr version of articles are essential to get directly to the point. As an heavy reader I like to have theses summaries detached from the article.
I agree but edw519 is a smart guy and I would give him the benefit of the doubt and assume he attempted to capture the essence of a "tl;dr" comment: short, vaguely corresponding to the material, and ultimately misleading.
I agree in principle, but I feel like the author might be missing the point; the reason "tldr" is used is because it has evolved as an efficient speech marker.
If you think about forum posting as a medium, then a "tldr" makes sense -- generally, you scroll down a list of messages. When you encounter a wall of text, you can either start reading (to see if you'll want to read the rest), or keep scrolling past until your eyes reach the "tldr" symbol, which draws you to the main "point" of the post without requiring you to mentally invest in reading the whole first paragraph.
I like how the first sentence embodies the very idea it is espousing. If you read only that sentence and close the page, you've still have taken away 80% of the information of the piece.
An important UI component for this technique to land: the first sentence must be short, and on its own line. Do that well, and a "TL;DR" prefix is optional at best.
I don't agree with the Douglas's interpreting an author's own writing of a TL;DR as answering the question of whether the author himself read it -- rather, it is pre-empting the question that might be asked by readers.
While it is true that it is entirely possible (and common practice) to provide the content of a TL;DR in the first sentence, it might not always be there. The reader can only know if the first sentence was a summary by first reading it (see the Halting Problem).
TL;DR is an elegant solution to this problem because it only requires five (minimally four) characters to be read to identify the summarizing statement, and then consume its content. And with the immense amount of content begging for my attention on the Internet, I for one appreciate being able to quickly determine if reading the article in question is something I will likely want to do.
100 comments
[ 3.9 ms ] story [ 182 ms ] threadThat only solves a part of the problem, though. Highly upvoted long comments on Reddit are particularly frustrating because so many of them have content that's weak or just plain wrong. I'm convinced that only a small fraction of voters actually read them.
I do agree that TL;DRs can be elided for articles that simply state facts or uncontroversial ideas.
Characterizing my opinion of writing as either something you 'win' or 'lose' is itself narrow (and frankly, almost insulting). I have to feel that you coming off this way is a byproduct of the Internet. I'm not trying to chastise you here. I understand that what I wrote initially might come off in a way I didn't intend, but you have to meet me halfway by assuming I'm not a total jerk.
Writing isn't about winning or losing, it's about sharing ideas. And yes, there are better ways and worse ways to share ideas. A conversation around a dinner table is probably better than an essay ever will be - but you can still try to get there. You can either hear this fact and say "aha, I should try to be more clear in sharing my ideas" or you can say "that's fatalistic, and writing isn't a game." I can't fault you for choosing the latter, but I do ask that when I choose the former you remember that I do it just because I want to be understood.
To respond to Fusiongyro's point that this is a narrow view I point out that generally in writing style should change with context. In some cases the author of the article is exactly right about summing things up in the first sentence, in others johnfn is.
TLDR: Whether to use tldr depends on what experience you're looking to give your readers, what you're writing about, and who you're writing for.
1. If you're writing a piece in which "the journey" isn't important, then you should put your conclusions up front like a good journalist.
2. If you're writing a considered, long-form piece in which readers' appreciation of your conclusions is path dependent then a TL;DR is obviously counterproductive - if it's necnessary for a reader to actually read the piece, it doesn't make sense to reward those who skip to the end or didn't comprehend what they read.
TFA took point 1, you and GP took point 2. Nobody (except Charlesmigli) has given an argument that TL;DRs have a place.
The "TLDR" is all-caps, so it grabs your eye out of the wall-o-text that you may be skimming over, and says "hey here is my basic point". And maybe then you'll go "hey that's an interesting point" and scroll back up and read their lengthy argument, story, or whatever, in all its labrynthine discoursiveness.
And now to demonstrate it I will include some lorem ipsum. Hipster Ipsum, to be precise. Swag polaroid tempor iphone echo park ethnic 8-bit, cosby sweater beard semiotics in. Magna organic neutra, exercitation laborum quis jean shorts aliqua ex eiusmod gluten-free pitchfork butcher. Cosby sweater disrupt keytar qui, beard pariatur lo-fi sustainable magna skateboard sint farm-to-table umami. Intelligentsia pour-over flexitarian, banh mi meh ad meggings thundercats ex. Labore tofu aliquip officia kale chips, bushwick single-origin coffee. Quinoa laborum velit 3 wolf moon placeat eiusmod, nisi brooklyn cred VHS stumptown. Gastropub try-hard intelligentsia, fashion axe 3 wolf moon wes anderson actually officia proident laboris american apparel do.
High life pitchfork ad tousled wolf, fugiat gentrify put a bird on it keytar nesciunt beard aliqua jean shorts post-ironic laboris. Flexitarian vice aliquip pork belly non, anim commodo eu. Dreamcatcher nulla cred, echo park church-key retro sint neutra vice mustache. Vero deep v art party, blog organic bicycle rights labore pinterest wayfarers polaroid quinoa jean shorts vice. Ad banh mi authentic art party. Trust fund et banjo bespoke portland. Cardigan disrupt american apparel aliquip kale chips non.
Craft beer vero cosby sweater kale chips ex nihil cardigan, truffaut authentic photo booth sed. Irony ethnic keytar post-ironic, ugh enim tonx truffaut before they sold out. Kale chips tattooed terry richardson keytar marfa carles artisan, sunt flexitarian vice ex. Umami sapiente direct trade etsy ut, hoodie readymade jean shorts brooklyn VHS cray polaroid. Anim pork belly swag minim. Master cleanse narwhal cred pinterest. You probably haven't heard of them wes anderson est, high life truffaut culpa stumptown ethical williamsburg vero sapiente.
Etsy plaid irony, brooklyn post-ironic williamsburg dolor butcher master cleanse pariatur aliqua next level cred. Seitan aliquip qui disrupt lomo literally. Sapiente tumblr laborum, gastropub bicycle rights non post-ironic pug ut. Do nisi narwhal, ad odio before they sold out disrupt brunch tumblr polaroid dolore +1 odd future. Viral officia readymade, plaid forage assumenda post-ironic cupidatat you probably haven't heard of them portland sint qui. Cardigan try-hard portland id selfies four loko, assumenda ethical letterpress aesthetic. Neutra non art party locavore aesthetic, actually freegan tonx cardigan godard ex gentrify.
TL;DR: One sentence with a block of all-caps beginning it sure catches your eye at the end of a long post.
http://en.wikipedia.org/wiki/Lorem_ipsum
I totally agree with TL;DR usage, it's a modern device for modern internet communication. People continue to use it because it's useful and works, not because they have an agenda to ruin the english language or are semi-illiterate. Possibly my favourite thing about it though is its lack of pronounceability. Its entirely invented and used as a written construct and is actually quite cumbersome to try to say out loud.
It's like a voting system. The ";" functions as the hash tag: "#tldnr", "#tldr", etc.
"T L ; D N R"
and
"... Too Long; I didn't read it"
Doesn't make sense. "N" does not pick out the beginning of any word. If you chance across the tag, your interpretation is less obvious than,
"... Too Long; Do Not Read"
The contraction makes sense, and thus the natural transformation into a meta-informative suggestion makes sense. Contractions serve to convey information, usually engendering more intimate dialogue. So it also invites the question of "why not"? And we all know how that goes. It invites the author and really any reader to a game not dissimilar to trolling, usually. It may not take a position necessarily, in terms of the message, and this is not required of what I am saying; however, an explanation of why one would post it at all stands in order. I think the conveying of information to other readers is also important.
Yes, of course I read it; but _why_ am I posting it?
A better argument against the tl;dr would be that the piece you're writing it for becomes redundant, provided it's an accurate tl;dr. The term tl;dr wouldn't be needed then, because the tl;dr itself becomes your piece.
If it isn't an accurate tl;dr, there's no reason for providing it in the first place, except maybe for giving a rough idea of what your piece is about. OP rightly points out, though, that conventions already exist for just that. A descriptive title or an introduction clearly distinguishable from the rest of your piece, for example.
http://www.quora.com/TL-DR/What-is-the-origin-of-TL-DR seems to offer a decent history of its early usage.
As a reader, prefacing that first line/paragraph with "TL;DR" means that all I'll have to read is just that part. This is useful because not everyone uses their first paragraph or sentence to outline the general idea of the article. For example, there might be an anecdote, or a quote, or whatever else to start the article.
When someone opens your webpage, they are entering into an implied agreement with you. They are seeking information and you are supplying it to them. If they are unwilling to uphold their end of the bargain by demanding a TL;DR from me without giving me the chance to read my words, I don't feel any obligation to satisfy them.
The other half of this implied bargain is that I simply offer what they came to find, and if I fail them in that regard, then I should be required to post a TL;DR because all 2000 to 3000 words I blathered out should be in 50 words or less. If I was able to offer a 50-word summary, then I would have simply tacked on an extra 25 words and eschewed the TL;DR.
If you don't like my attitude, that is fine. You probably aren't my target audience, and this is fine. The World Wide Web is a very large place.
I think the feeling is often "I made this so long because I did not have time to make it shorter."
Of course on the web, this is short-sighted and self-defeating. If you have a valuable thought that you commit to the web, you do so in the hopes that it will be read many, many times. You only have to write it once.
So to agree with dizzystar, respect your (potential) readers and spend a little more time making that thought concise.
I love it when I receive emails from readers asking me to clarify some point, or telling me about spelling errors. I also get requests to remove paragraphs. After about 5 minutes of pondering it, I find that they are usually right. It's not that difficult to delete a paragraph.
http://articles.chicagotribune.com/2009-11-08/news/091107024...
'A reader of "The Elements of Style" once sent E. B. White a clipping of a book review that misquoted William Strunk as having advised writers to "Use less words!" White wrote back: "I often wish Strunk could come alive so that I might hear the gnashing of his teeth."'
If paraphrasing Strunk he deserves a grammatically correct quote: "Use fewer words."
http://grammar.quickanddirtytips.com/less-versus-fewer.aspx
// As noted in a sibling comment, the actual quote is "Omit needless words."
http://www.bartleby.com/141/strunk5.html
Oh yeah, totally write like Hemingway if you want the internet to pay attention.
It was: "If you summarize your idea in your first sentence, writing "TLDR" is superfluous."
He wrote the TLDR summary, he just didn't preface it with TLDR.
That to me is the great thing about this article. He's following his recommended practice to illustrate the point.
- Author should summarize their idea in the first sentence of their writings.
- Prefixing this summary with TL;DR is useless and asinine as it stands for "Too Long; Didn't Read".
http://tldr.io/tldrs/50f34acc3ea2fa3e06001f25/tldr-is-unnece...
If you think about forum posting as a medium, then a "tldr" makes sense -- generally, you scroll down a list of messages. When you encounter a wall of text, you can either start reading (to see if you'll want to read the rest), or keep scrolling past until your eyes reach the "tldr" symbol, which draws you to the main "point" of the post without requiring you to mentally invest in reading the whole first paragraph.
An important UI component for this technique to land: the first sentence must be short, and on its own line. Do that well, and a "TL;DR" prefix is optional at best.
While it is true that it is entirely possible (and common practice) to provide the content of a TL;DR in the first sentence, it might not always be there. The reader can only know if the first sentence was a summary by first reading it (see the Halting Problem).
TL;DR is an elegant solution to this problem because it only requires five (minimally four) characters to be read to identify the summarizing statement, and then consume its content. And with the immense amount of content begging for my attention on the Internet, I for one appreciate being able to quickly determine if reading the article in question is something I will likely want to do.
TL;DR: TL;DR != opening sentence