i thought this was already done? i cant seem to find it.
the idea is that a user isnt allowed to post on a another users thread if the posting users "bans" or blocks the other users from doing so. i think the option was that another user had to put a user on ignore, than that would prevent the replying user from posting in the posting users thread, which would like stop fighting and bickering.
I have seen mods to allow mods to ban users from thread, allow users to not allow others on their ignore list to view/reply to threads, and allow users to pick who can/cannot view/reply to their thread. All these mods can be found by doing the search I suggested.