I didn't wear a helmet last Monday, when I rode home from my office (22 miles). The commute is long enough that I load the bike, cycling clothes, next day work clothes, and two lunches into the car, so that I can leave most of that at work and ride unencumbered. Guess what wasn't hanging on it's usual spot from the handlebars? Yep. It felt really weird riding without the helmet. It's about 1/3 residential streets and 25mph "Parkway" riding (follows a creek, plenty of curves and wet pavement) and 2/3 virtually unused MUP.

I found myself on the brakes a lot more than usual.

My wife works with program management for brain injury specific recovery programs in Maryland, so I, of course always wear a helmet... except that once. Also, this is why I'll never (be allowed to) ride a motorcycle, helmet or not.