It seems that more aliases than not tend to inadvertently out themselves via world chat, which is what Mike alluded to at the very end of the post just above.

You'll often see Alias A start defending a questionable trade by talking about one of the players he's dealing to Alias B, and then a little while later continues the conversation as Alias B referring to that same player as "his" player that's being dealt. A common slip-up as in the heat of the moment they forget which persona they are posting from. I've seen that happen more than once. It's virtually impossible for them to explain their way out of, and they often just acknowledge that they've been outed, and they agree to go away quietly.