That's kind of the very definition to "TL;DR". Personally, I think they are an atrocity, because if everything useful in an article could be distiller to a tweet, it should have been a tweet and not an article that made it to the front page of HN. I don't downvoted them, though (unless highly inaccurate), because they may provide use to some people in deciding whether TFA is worth spending their time on.
A distilled TL;DR is, as you say, either useless or an indication that the article is unworthy.
I prefer the commentary form of TL;DR which is a pithy remark that allows people who are already familiar with the subject to learn what biases or novel facts this article displays. For example, consider the fictitious article:
Are Human Ears High Resolution Signal Detectors?
which discusses a study of microphones, digital audio recordings and double-blind human subjects trying to distinguish signal in high-noise environments.
A useful TL;DR might be:
Human ears suck.
which might be a useful indicator of whether you're going to learn anything new from reading it.
I have to tell you, I love TL;DR's, maybe I've got a form of digital ADHD but I just want to get the content in a quick, bitesize chunk. Especially when its something like this that I'm not particularly passionate about.
Whoops, yes. The original wording of my comment was the definition of TL;DR. The point I was trying to make is that in this case, the first paragraph of TFA was its own TL;DR, so GGP was particularly redundant.
