Can we agree that helmets do provide some level of protection? If it's just from a slow-speed head-pavement crash, it's still protection, correct?
If we assume that helmets do provide a small level of protection, would it not also be safe to assume that some people have those types of crashes for which helmet use is designed?
Can we then assume that every cyclist is at risk of that type of crash? I'm not saying all cyclists will crash that way, but we are all at risk, just as we're all at risk of being hit by a car.
If we're all at risk for a specific type of crash for which a helmet could save our lives, would it not be prudent to wear a helmet?