I haven't really had a problem with this perosnally, however I first noticed it when I replied to a post and then quoted another post just to realize it was in place. After checking a bit I figured out what was, no biggie but maybe it would be a good idea to inform that user at the time of the bumping. Something in a bold font that says "your topic will not be bumped within a 24 hr period, only appended" just a thought.