When copycats strike - what should the community do?

Recently, an issue of plagarism came to light on the Miss Exotic World forum. Essentially, one well-known performer with an equally well-known and documented act found out that another burlesque performer in her area had copied her well-known and documented act and was performing it at a local venue. She approached the copycat on civil terms and asked her to stop, and was assured that the bad behavior would, indeed, end. It did not. The well-known performer turned to the community via the MEW forum, explained the history of the copying, and asked that if others in the community saw the copycat using her well-known and documented act that they let her know as a way of protecting her work. This is a brief summary of events, feel free to read the full story over at the Yahoo! Group.

What should the community do when copycats strike? Obviously, no one wants to out their fellow performer, but is there a certain amount of policing that the burlesque world needs to do to keep its creative product safe?