Maybe offenses should adjust and not put their WRs in position to get hit like this. Not saying it would eliminate all of the hits, but if you don't want to get jacked up, don't run across the middle in front of a safety or LB.
I remember when Darren Woodson knocked that guy out for Seattle. Everyone was blaming Woodson, but I blame Holmgren for sending that guy into a pattern right in front of a safety that he knew would knock him into next week. It is a dangerous area to run a route and not everyone can handle it. That is part of the beauty of the game. Seeing guys that have the stones to run those routes knowing they could get knocked out and seeing the defenders stake their claim to that area of the field.
I understand the desire to protect the players, but this change is just going create another disadvantage for the defense.
Guys like Desean Jackson are fun to watch, but at his size, it is just a matter of time before he runs into someone much bigger than he is and he's going to get knocked out. You can change all the rules you want, but it is still going to happen.