honestly, i feel naked not wearing a helmet, however i cannot remember not wearing one. we are exposed to enough risk during the course of a regular work day (i do production longline work), why wouldn't you try to mitigate those risks by protecting yourself.
there was an accident a few years back when a 206 pilot in canada found his head to be firmly lodged between the front door pillar and the ground, and all he had to do to extricate himself was undo the chinstrap. there are many other stories how helmets have saved lives.
but lets also not forget about how they protect your hearing from high freq noise penetrating the nape of your neck.
wear one to protect your head and your medical and lets let the debate rest.
in case you wondered, this is what i think of my helmet:
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