I saw two minions of the law, push-bike variety, in Wollongong today, and I was struck by the helmets they were wearing. They were very 'space-age', angular both front and rear. Now motorcylce helmets are smooth in contour, both for aerodynamics, but also so they don't 'grip' the road and reef your head around if you fall off. I know the speeds are lower for pushies but surely their helmets ought to be smooth too, for the same reasons???