it wont cut down anything... as said before, you do not need head contact with anything to get a concussion... if you are moving 5 mph and get hit right in the stomach and stopped, your brain inside your your skull will still be moving at that momentum, then when your head stops moving forward, your brain smacks the inside of your skull, causing a concussion...

blatent helmet to helmet sh!t is bad, but you cant take everything out of tackling... things ARE going to happen, regardless of what you do to try to stop it...