I'm trying to make a duel only server. So far, this isn't really possible with tf2 because there's no real way to limit the players on each team to 1.
I'm also looking for a way to have a real fraglimit in tf2 so you can have set score limits for duels to 20 or whatever.
(btw mp_fraglimit doesn't work for tf2. all the team balance cmds dont really affect the overall max players per team)