Ironically enough, the excess of concussions nowadays are due to overly protective gear. It gives them a sence of protection that leads to more violent tackles, which then leads to more violent headshakes.

It's like when they introduced gloves in boxing. Pre-gloves, it hurt like a motherfucker to hit someone in the face. You'd have just as big of a chance to break your hand as the opponents jaw. So they had to make the gloves 'hurt' again by making them thinner.