Yea he's a goof but that why I like him. I would love for you to say that to him face-to-face though. Haha. He would tear you up. There's no point to judging a fighter on his personality though. He's a fighter. Focus on the fighting ability, because when it comes to BJ, there's a lot of it. He's not on TUF so he's not trying to make friends or impress you with his snappy comebacks. He's there to fight and I highly doubt he has a care in the world if someone thinks he's a dork for what he says prefight and postfight. His fighting abilities more than make up for his goofy personality.
I think a lot of fighters are goofy, annoying, or whatever but that's not why I watch MMA and the same should go for you if you are a true MMA fan. Remember this isn't The Real World, it's full contact mixed martial arts.
Also, for the record, BJ could probably beat Wanderlei if he can avoid at least a few knees, take him down, and keep him down because Silva loses all of his fights when he gets put on his back for most of them and I don't think BJ would have too much trouble keeping him down there.