I myself don't even see the teams before I join. I always pick random, and I think Noble does this as well. If I notice the teams to be one sided towards my side, I back off and play scout and just run around. If people shoot at me, I'll shoot back. Otherwise I just run. If my team isn't doing well at all. I choose a class that isn't taken and I take my time and do one kill at a time. Eventually, especially if you are attacking on Dustbowl, they will weaken. With spawn times high for the defense team you can really come back on them. When red has 12 players and 4 engies, it seems impossible, sure. All you need though is a good sniper and a charged kritzkrieg with a stickybomb demo who is competent and you can decimate the enemy team.