They have the technology, is it time for admin to do something about these?
Perhaps they could ban later usernames attributed to the same person, failing that how about posting up a list of who's who, so then at least everyone knows who (relatively speaking) they're talking to.
Perhaps they could ban later usernames attributed to the same person, failing that how about posting up a list of who's who, so then at least everyone knows who (relatively speaking) they're talking to.