NFL collisions are brutal. And it's not just the collisions. I remember as a young guy being on the sidelines at an Oilers game. The tight end, Alvin Reed, was running full speed towards where I was standing. He stretched out in the air, doing everything he could to catch a ball that was just a bit too far. He missed the pass and smacked HARD into the ground and, with his arms still outstretched, slid a few more feet. I can still hear the grunt and impact with the ground. SMACK! Alvin got up, looked at me, and trotted back onto the field for the next play. That REALLY had to hurt, and there was no other player involved. I knew right then and there that I wasn't cut out to play tight end.I hope you're right but the shelf life of an NFL player is much shorter than MLB or NBA because in those sports you don't have a 300 lb guy doing everything he can to push your face into the ground every game.