When I bump a thread, I usually forget about it... It ends up going on the third page of my search for my started threads, and I never remember to respond to it. How about when the post is bumped in the forum, it also bumps it in the started threads search results? Just an idea.
And how can I remember the last time I bumped my thread? I know maybe that sounds stupid but it's true. I can't remember how many days has been past since the last time I clicked "Bump"
You can bump a thread as long as it's done via the "Bump" button. You can't bump a thread by posting to the thread. If you don't know how long it's been since you hit the "Bump" button, hit it again... it will tell you.