OjPimpson does the same thing, but I just use /watchall all the time anyway so once I spot one of their names, all of the subsequent names wont matter. I'll see them all as they login after a game ban. If people would use /watchall, these types of things wont be an issue once you get use to using it and notice login habits, etc. And even if you arent good at spotting them, just obs anyone you dont know and if they act up, just remove them from the game since they are obs. Or simply tell them to log in with a known name. Kinda simple really.