OK, so say I post a response in a GQ thread, and then someone comes along later and either posts additional information, or responds to a question I asked. Is it considered good form to reply to the thread again to say, “Hey, thanks for answering the question!” or, “Hey, thanks for providing that interesting info!” or would it be better just to keep quiet and let the thread die a natural death? I am never sure about these things.
I think the official position is “kinda sorta maybe”. Normally, if I’ve asked an extra question in somebody else’s thread, I would thank somebody who has devoted a whole post to my question -especially if it’s obviously been researched. If somebody answers my question as part of a general post, I might not bother, hoping the thanks are implied. If it’s an unimportant question, you could just do the “thanks in advance” bit in your first post. But if I start my own thread, I’d feel it very bad form not to come back with a “thank you”, or at least a comment, especially if there are thirty or forty informative replies to it.
so now would it be expected of MsWhatsit to come back in here and thank TheLoadedDog ?
MsWhatsit, we’ll follow your lead…
This small matter of etiquette is a matter which concerns me also, and I am wondering what is an acceptable timeframe for returning to a thread, and expressing this gratitude.
If it is left to me, I will say five minutes is too fast, and two years is too slow, and I choose something in between, although I require guidance here.
I know we had a discussion of this some time ago, but I can’t find the thread.
I believe the consensus was that if the thread is active, it is a nice thing (though not necessary) to pop in and thank those who responded. However, if the thread has been inactive for a while and dropped off the board, just posting to thank the people who answered is unnecessary and just displaces a current topic from the front of the board.
Thank you for your interesting inquiry. 
Gotcha! Thanks for the responses, all. 
I know this is a bit late but I don’t have a computer over the weekend. Anyway, here goes.
I have noticed some good and experienced posters often tend the threads they have started, come back every day or so to check what’s been left and acknowldedge the offerings. And I think some valued thread-starters are often able to add a bit more every time they do this tending. A little more background, an anecdote on how they’re dealing with the situation that kind of thing. It’s like ensuring that the audience gets good value for money and will continue to tune into your threads.
So that’s what I try to do on the rare occasion I start a thread.
I think if you read threads by the well-loved Scylla you will see this principle of “return with a small bonus”
(Except in that ewes thing, of course. That was just sheer terror all the way…)
Redboss