We're gonna try something out to remove ambiguity. You know the little "topic icons" that appear up at the top of any post you write? Those aren't only for the first poster in the thread—they can also be used in any reply, as well. So, here's the new rule:

When you are finished with a thread, and have made what you consider to be your final post, use the waving checkered flag topic icon ( ) so that everyone will know you do NOT intend to post again.

It won't lock you out from posting again—if someone unexpectedly does something you want to reply to, go ahead. Just be sure to use the checkered flag icon if you think you're done again. Capiche?