Premades should just say "Premades!", so they fight another premade team.
I've seen sooo many games with "3v3, anyone!", and then watch as the host has his buddy, allows only another high rate win guy on his team, then kicks anyone with a high win rate on the other team.
The sad part? I've watched a lot of "good" players do it. Are we that cowardly? It's a GAME! Who cares about your numbers? If you're a fat kid drinking Mt.Dew, a stacked win ratio won't help that. (Switch to diet, it's the first step).
Feel free to join my game, I usually call it "no retards". Come in with "but... but... they have a 2% advantage over us, and I want to be on that team, and and.." <kick>
Have fun, if you got a noob, try to talk to him reasonably. Teach him/her.