Actually I didn't mean to rise the question of violence in video games. My point was that games won't make a differnce in your guitar performance.
Still the question of TV and video game violence is very arguable. I watched on the TV about the following case -- a kid in the kindergarden slammed another with some heavy object and was quite surprised when his fello didn't rise(like they do in Tom&Jerry). I don't think however that the TV is guilty, but u see ****s indeed happen.