It's almost like the ATM. You can only take out so much on a particular day. Perhaps a community user can only provide up to 2 negative points(and consider the same for positve feedback) to any one user at any one given time, or any one given workspace/discussion. Another thought, is provide a "cooling off period" for those that have been "shown the door". They are only welcomed back after a period of time away, 30 - 60 days; or something like that. I am always for giving someone a "second" chance. If I'm not mistaken we have posted a "protocol" for requests submitted to this site. Perhaps it needs to be more front and center. Bottom line I agree with Jim, limit the amount of negative feedback one person can give another in one fell swoop.