I change at work -- my bike commute is 10 miles with a 30-mile train trip in the middle, and there's no way my shirt is going to stay freshly starched after an hour of Seattle rain.

If I rode at a Dutch commuter pace on a sit-up-and-beg roadster, I could use a cape and an umbrella and stay dry enough, but I'd be adding an hour or more to my commute.

I keep dress shirts at work, use the cleaner across the street from the office, so shirts don't have to ride back and forth every day. Likewise ties, coat, etc. Pants get rolled to stay well-pressed in the bag, along with a fresh undershirt, underwear, and socks.

Changing takes maybe two minutes in dry weather, five minutes when it's dripping wet and I need to dry my hair at the office. (Short, clipper-cut hair makes that easier. The lack of an employee locker room keeps all the women cyclists I know at work in their cars in the rainy season, late September to June.)