This strategy allows you to actually help your team as a traitor medium. However, it requires the presence of a non-traitor medium. Basically, after the first townie dies, you can pretend to be two people in the night chat at once. Say "Hi, I'm (your name)" and then "Hi, I'm (your mafia buddy's name)" and pretend to be two people. Then, the non-traitor medium and the dead townie will confirm you and say that there are three members, making all three of you "confirmed mediums". Continue to pretend to be two people for the rest of the game. This strategy falls apart if you or your mafia buddy that you're trying to confirm dies though.

As townies, to counter this strategy, always be suspicious if there appear to be 3 mediums in a game all "confirming" each other, especially if there isn't room. Also, if you're a non-traitor medium, question one of the other medium claims in a whisper asking exactly what the dead said last night. If they're unable to answer or if the other medium has to whisper to them first, you know that BOTH of the other medium claims are likely to be evil and following this strategy.