EDITOR: I'm from Boston, where the joke is that traffic signs are mere suggestions. The first time I visited San Francisco, I stood at a crosswalk on Marina Boulevard, eager to cross to Crissy Field. I was stunned when four lanes of traffic came to a stop. I thought maybe in my excitement to take the beautiful run down to the Golden Gate Bridge I'd forgotten to put my shirt on. I'd never experienced anything like it.
It seems odd to present East Coast traffic patterns as a model. But I would like to suggest that pedestrians look both ways before entering — and proceeding through — a crosswalk to be sure cars are indeed stopping. Do not rely on a human crossing guard, flashing lights or yellow paint to protect you.