How about making adding to a PM only available to Mods and Admin?
You can imagine users, slagging off another member,
drawing in someone and then, just for the hell of it
invite in the member who was being slagged at.
I don't think it could be trusted to be used correctly
at user level.
Admin Mods and Topic Starter is the adder i think could work.
Well we like to think so.
