A driverโs helmet is a form of recognition, much the same as coats of arms in medieval warfare. โLion rampant on gulles, with bend sinister argent, hold your fire lads, heโs one of ours.โ
Mike Lawrence
A hard hat added weight to the head and so increased the chance of serious neck injuries. If your head was going to hit a tree, youโd be dead in any case, a helmet made from compressed cork was not going to help you.