BUT, your saved life was offset by a friend of mine who was decapitated when her helmet caught as she slid under a guardrail. Had she not worn her lid, she would probably still be alive today. There have been thousands of lives saved by helmets. There have been a few hundred more than that taken by helmets.

Now, the same doesn't apply to cagers. A properly belted occupant in a car can easily sustain serious head injuries that would be reduced by a helmet. At the same time, most of the conditions tht can make helmet use more dangerous than safe don't exist in a cage, so it is an all-win situation. Yet, not only are there no laws requiring helmets in cars, there are some that prohibit it.
I still say that, whatever is the real motivation for helmet laws, it is nothing to do with safety or they would be required in/on all vehicles.

Let's hope there's intelligent life somewhere in space 'cause it's buggar all down here. -- Monte Python