Beware of the malicious price drop exemption. Aggressively priced cards should not be allowed to be bumped more frequently due to a nominal price drop.
If an interval is decided upon, it should be applied to all listings regardless of price drops, content manipulation and whatever.
All listing changes can be accomplished by editing the original listing ( and title if one chooses ) without bumping the thread.
All of the above would be easy to police simply by checking the post and bump dates.
How to manage chatter bumps, as in the Lenox Cobb listing, is an entirely different issue and a blanket rule could be difficult to formulate. Incidental chatter that results from the ingenuity of the lister should not be persecuted in my venerated opinion.
