You are sane and obviously don't understand the people around you. Talk to them and you'll find that they all parrott the words: "I know a helmet won't prevent injury in ANY accident, but it will work in most."

Here's the problem - a helmet absorbs a TINY amount of energy compared to what is on tap in an Arty Johnson fallover. What saves people is the way that the human body is constructed - The head is pretty carefully protects by shoulders wider than your head (discounting of course Clint Eastwood), reactions that cause you to twist your body in such a way as to protect your head in a fall and that sort of stuff.

I know that I wear a helmet because I'd just as soon not whack my head and have a lump, abrasion or perhaps even a concussion. To me that's important because those are the sorts of injuries a helmet can prevent or mitigate.

Myu objections to the helmet hysteria is that it ends up completely masking the real dangers in bicycling and nothing ever gets done about them because it's MUCH easier to blame the victim.