[Lazamataz]

Is it because the longer a posting and thread comments are on, the less likely more people will see it because new posts are going up all the time and it slips further back in the pack? It's just a way of pushing the posting back to the top of the pile so more people have a chance to see and comment on it?

Yes.

[HotHunt]

Okay, I understand "it" now.

But another dumb question, does posting "Bump" or "BTTT" in the reply box, automatically force the posting back to the top or is there some other mechanism that does that? How does the mechanics of it work?

Thanks for your patience with my ignorance.