I really disagree with you here. Punt returns especially are very dangerous compared to running the ball from the backfield. In some cases, you have a guy with 40 yards of steam charging at you as you look up for the ball. If you fail to move or make the fair catch signal, you are in a world of hurt like many of Steve Tasker's victims.
Blocking on returns, while is dangerous isn't the the reason Kevin Everett was paralyzed. He made a tackle on Domenik Hixon and hit him in the wrong way. In this case, the return tackle was harder than the hit the RB's generally take.
Mike I respect you as a poster, but please get the facts straight.