Maybe this is why I'm SO good *rolls eyes* at Halo 2:
http://tiedtheleader.blogspot.com/2006/02/this-is-your-brain-on-halo.html
Seriously... everyone is different so I don't think the article's point is true for all gamers, but it's true for me. When I'm just having fun, and even goofing off in a game, I tend to play better (and I sometimes stop goofing off). Plus in real life, I'm a pretty laid back person and not much bothers me, so that explains why I'm SO good at everything in real life *rolls eyes*
Here's another short article about taking your personality into the game: http://tiedtheleader.blogspot.com/2006/02/residual-self-image.html. "I can safely tell you that a drawer filled with Killtacular medals does not amount to ability to kill an orange frisbee as it tries to escape your scatter of shot".