Maybe a view of Mikael Colville-Andersen's TedX talk would be beneficial here. I know it entails 16 minutes of thought, but if you care, maybe you should watch


a worthwhile read is the wiki entry

http://en.wikipedia.org/wiki/Bicycle_helmet

it includes sections on history, standards, design intentions, fit and care, criticism of current standards; new designs, required use, risk, desirable and undesirable effects of use, opinions both for and against use, and a list of references