Think about this, lineman get hit on nearly every single play yet I would venture to guess that they experience the least amount of concussions.  The distinction for having the most concussions has to go to WR's and defensive secondary.  This tells me that space to generate more speed and higher impact hits also increases concussions.  Changing the rules of the game to favor the passing attack and create more space has directly resulted in an increase in concussions.

 

Couple the above with the fact that not only are players getting bigger, stronger, faster on average but the awareness of concussions and the crackdown on protocols for concussion treatment have sharply risen brews a perfect storm for an increase in reported concussions.  I only played high school football but can guarantee I had at least one concussion and saw some of my teammates get concussed as well.  Back in the late 90's we just saw it as getting your bell rung and were told to get back in the game.  Only once did I see a kid get held out of a game and that was because he was talking nonsense and vomit on the sideline.

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