Thought I'd revive this thread for a moment with two new things I've discovered:
1. Just, uh, theoretically... I mean, "my friend" might have done this last week...:
When you are an idiot and decide to go way too fast down the hill through Frick Park on Forbes when it's just rained, and then you throw yourself at the asphalt at like 25mph or something just past the intersection at Forbes and Braddock, you don't get hurt nearly as badly in winter clothes as you would have if you'd been wearing shorts. You may still have some pretty interesting scrapes and some positively enormous technicolor bruises, but they'd be a lot worse had you not been wearing two pairs of tights. You know, theoretically.
2. Studded tires are heavy and make me even slower than I already am, but that means that when I put my normal tires back on this week, I was suddenly significantly stronger and faster than I had been previously, since I had been compensating for the big increase in rolling resistance from my studded tires for the past few weeks. This was fun to discover.