Ed, you are correct. Yet we disagree.
I'm not saying that comments don't provide useful pieces of information to the world at large, searchable and present for future generations to read. Of course they do. I'm not saying (as other commenters have sad) that comments have no value. Every now and then I get some really good pieces of information from comments. But total value and net present value are different concepts.
Case in point: I made the parent comment, then logged off. Today I'm pretty sleepy, so I am having a hard time focusing. 15 minutes later I'm thinking "wonder if they downvoted me over on HN?" so I pop back over. What?!? A score of 15? Perhaps it was because I prefaced my remark with "you guys are going to kick me in the ass"
Take note of the comments. Most, as usual, miss my point or are trying to argue some other point. I have found that when I post a comment read by 10K people, 40 or 50 will take it the wrong way. These are folks that if you try to engage will just argue with you. Close the window.
Ten minutes later pop back. Score up again, eh? There might be a good discussion that hangs off this. Bears paying attention to. But must get to work. Close window.
Five minutes later, back over here again. See your comment. Well heck, I'm not saying it's all bad. I should type a pithy response. Ed has a good point.
Yes, to future generations who are googling for specific data these conversations are going to be a goldmine, hopefully. For us, every now and then, you get something awesome -- just enough to keep you participating.
But overall does the participating directly relate to the work you have planned for yourself today -- programming, hiking, reading, whatever. Or when you find a "goodie" do you use it to justify all the time spent? It's the Facebook question -- people you like, giving you pieces of information that from time-to-time are valuable, letting you feel part of a group -- something good for you or something sucking you in?
Future generations, sure. Getting things you can find nowhere else? Absolutely. But in the present sense, in the next hour, for the next minute -- best use of time? Am I selecting to use it, or is it (and the great people who participate!) sucking me in and then I'm rationalizing?
I can't answer the question for others. Took me a long time to figure this out for myself, and as I am now showing, I am not very good at listening to my own advice :)