So you guys are saying that helmets aren't supposed to protect you against concussions? What exactly are they for then? It's funny that every time someone falls on their head with a helmet on, the assumption is that the injuries would have been much worse without it. Okay, sure, it must have absorbed SOME of the impact energy, but how much exactly? Is it okay if the helmet absorbs only 5 percent of the energy? How do you know if a helmet is doing its job unless you volunteer to land on your head once with a helmet on and once without? Otherwise, the amount of protection offered by helmets is somewhat speculative and the helmet worshippers will claim that surely your head would have exploded into a fine mist without it.