Once per year on a warm Spring day, I would grant myself a nostalgic ride sans helmet out in the countryside.
Never, ever again will I do that.
Why?
I had a bizarre crash last September landing on my left side, cracking the helmet pretty good. Broke left hip bone (torchanter), 5 ribs. collar bone, scapula, humerus in 3 pieces, left elbow and they had to surgically break my ulnar to put me back together. The Trauma team could not believe my head was ok, they said you must have had a really good helmet. It was the top of the line Laser MIP, it now in the landfill.