I'm an atheist, so I don't easily believe in stuff without tangible proof that I can see, and that I can replicate. In my opinion, the statistics about adding hi viz clothes don't lie. If studies have shown that wearing hi viz reduces your likelihood to be in an accident, I believe them. While the studies don't conclusively prove causation (just correlation), I think a strong case can be made that hi viz reduces accidents.
In my own experience wearing a yellow Aerostich jacket, I have had drivers pull up next to me to check out my jacket and lift their sunglasses to see just how bright my jacket is. While it won't save me in every case (much like a seatbelt or airbags), if I have to make a pick, I'm rolling with the odds that say hi viz can help and backing it up with good armor and a sturdy helmet.
It's a belt-and-suspenders approach really; hope for the best (be visible and avoid an accident) and plan for the worst (armor and a helmet). Life is too short and too precious for me to accept any more risk than necessary. You can wear whatever you want (it's your life to risk), but as for me and mine, hi viz is the way we roll.
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