Who knows, maybe wearing a helmet caused the break in my C-6 along with the compression and slippage of my C-5/C-6/C-7 when I hit the ground after being ejected from my bike 3 years ago. Who knows, maybe wearing a helmet prevented injuries when my head bounced upon hitting the ground after falling over doing a track stand or the time a friend clipped my front wheel at a slow 18mph and again my head bounced off the ground or when I dumped at 25.2mph during a roundabout encounter in a triathlon.
Can say for sure that the TBI my wife suffered when we were stopped at a traffic light and were rear ended by a car doing 60mph happened without hitting her head on anything in the car and just maybe, having the extra weight on her head from a helmet might have caused a neck injury.
Who knows**********?