I would agree with the comments Dr. Gordon made earlier that rules are in place and virtually every sport has had changes in rules. The automatic red card for an elbow in soccer is one that comes to mind with me. That changed the incidence of concussions in that sport.
Every sport has rules. It's a question of enforcement. That is a challenge. Referees are under a lot of stress.
We still have Hockey Night in Canada and the NFL opening up with these massive hits. I can say sitting on the sidelines that there still is the culture in a collision sport that when a player makes a significant hit, there is enthusiasm and almost pride in it on the sidelines, which is going to take time to change.
Also, one of the challenges is the glorifying of these hits in the media all the time and personalities putting out tapes that just are a collection of these hellacious hits. When the pros actually take pride in it, there's a trickle-down effect to the grassroots.
Part of it is going to be changing the culture.