James,
You make some valid points and, in general, I agree that one of the things that has made this forum so agreeable
(most of the time) has been the sort of informal atmosphere, which is due in part to the mixture of on/off topic posts.
OTH, the ratio of OT posts has gotten so high, that I honestly believe it’s a major contributing factor to the decline of more seasoned posters. (And lets face it, traditionally, the majority of OT posts come from people who stick around here from 1-1.5 years or so (Amar aside :roll: ) No one here is more “valuable” than anyone else, but when a forum loses more and more of it’s more experienced members , for whatever reasons, it’s a loss for everyone.
I also think that with so many OT posts, and a less than perfect search function, the board becomes much less user friendly to brand new users who are looking to gather information on specific things.
Finally, from a personal standpoint, I find myself with less and less free time, and while I’d like to be able to continue to read and contribute to the forum, it’s gotten to the point where I really is difficult to justify, there’s just too much stuff to sort through. And when it comes to contributions on a technical level, I have become unwilling to spend the time to write thoughtful detailed posts, because I know that before more than a few days, what I’ve written will be pushed so many pages back, that it will not be useful to more than a few people, so why bother?
Personally, at this point, I much prefer the Highly Segmented forums, like the various acoustic guitar forums, however I realize going to that extreme is probably not the best answer for our little neighborhood here. Still I think and OT forum, and a Buy/Sell (Marketplace) forum, wouldn’t hurt anything, and would help out quite a bit. Just my opinion, of course.
Dale,
Thanks much for taking the time and effort to solicit feedback and consider the issue, it’s much appreciated. 
Loren