My point is that, while helmets may or may not save some lives or injuries in certain instances, (John obviously feels his accident was one), they are shown time and again to be really peripheral to bike safety. Unless someone can show me how helmets actually prevent accidents, from Andre's quoted statistics we can assume that no more than 13% of the cohort were wearing helmets. Thus, the vast majority of cycling trips made (by people in that study, at least) were perfectly normal with no traumatic events.
My assertion is that, by dissuading people from riding (for whatever reason, be it obstinacy or fear of "helmet hair" - a particular reservation amongst female would-be cyclists), compulsory helmets can actually have a far worse effect on personal and public health.
As I mentioned before, this debate often boils down to the effectiveness of helmets, when that is really not the issue. Since there are numerous ways to die in a bike accident, should we be made to wear Kevlar jackets, gloves, anti-skid pants, shin and knee guards, eyewear and other PPE? A few more injuries may be prevented, but MANY more people would be dissuaded from cycling. This is the basic error in these government initiatives.