Me too, it's a different attitude and risk.
My stats:
14 years of daily commute to work, 1 fall (a broken chain on a power standing starting, painful, no help from helmet there)
~25 years mountain biking, 2 broken helmets, 3 bones, many many cm of skin lost.
Slashdot Mirror
It's race cars engines
Not a scientific paper, but... https://www.youtube.com/watch?...
And need to be warmed before starting, due to very tight tolerances.
Simple reason... http://www.amazon.com/Haribo-Gummy-Candy-Sugarless-5-Pound/dp/B000EVQWKC (check the reviews)
I'm usually in cross country rides, marathons and orienteering, it's all ways with helmet, gloves, some experience and luck.
Me too, it's a different attitude and risk. My stats: 14 years of daily commute to work, 1 fall (a broken chain on a power standing starting, painful, no help from helmet there) ~25 years mountain biking, 2 broken helmets, 3 bones, many many cm of skin lost.