No one ever really believes in how valuable helmets are until they have personally smashed their second helmet .. and walked away.

I've ridden a bicycle now for fifty or so years. I've driven a taxi for the disabled carrying wheel chair passengers who fell over skiing or in the bath or while having sex and every other activity known to man. Bike riders did not figure prominently in the wheel chair population. My contact in a hospital emergency room says that it's because they die because of many things but often because of massive head trauma. He won't ride a bike any more but thinks helmets are sensible. I would like to see more data but can't find it. Yet. Traffic has changed in the last thirty years. Life is more intense, faster and roundabouts are not for the faint of heart. I wear a helmet. After an unavoidable collision with a stray dog, helmet number one was destroyed but my head was intact. During an unsatisfactory shoe clip disengagement when stopping, I fell over and totalled another helmet. [I now no longer use toe clips.] OK - my fault you may say. But humans do make errors. So, tell me - how many times does this have to happen before I say to myself helmets seem like a good idea. A seriously good idea.