He says that MLB is a different breed and it "begins at the high school level when a young teenager first experiences the joy of contact football. The fact is that when you receive what I would refer to as a partial but playable concussion, there is a unique feeling of being high, of floating, of being numb to pain and unaware of other distractions. This produces a happy state that translates to a belief of invincibility and a superman complex. In some ways, it acts just like a drug. You become addicted to that feeling and want more of it. And when you get another hit, it feels even better. When mixed together with the newly found testosterone being produced at that age, it is a special and hidden pleasure. Very few young football players are attracted to this kind of behavior. Coaches are mostly unaware unless they had been middle linebackers." Very interesting read - and nicely written. Lots of great stuff in there.