Hi
I have an argument with our HSE inspector here on the farm every year. He reckons I should wear a helmet on the quad bike as it's dangerous not to. IMHO this is rubbish... if I come off my quad around here I hit dirt as there are few rocks (grassland dairy farm). However, with a crash helmet I increase the moment on my neck and a broken neck due to a fall is more likely. It also reduces situational awareness ... which in itself may contribute to the likelihood off me coming off. So in this case you could justifiably argue that wearing a helmet is actually MORE dangerous than not.
Has this anything to do with wearing a helmet in an aircraft? Possibly not ... but it does show that just because it is perceived to be safer, it doesn't mean it always is!
SS