There is a lot of talk out there in the bicycling world about "subjective safety" and how your level of it will determine how much, or if, you will ride. I hear people say that San Francisco is too busy, too crowded, too unsafe to ride. Perhaps for some it is, but for these folks, this is not the case.
Some can let go of the reigns from time to time.
Some can let themselves just enjoy the ride from the front seat.
Others are able to let themselves be comfortable anywhere, anytime. Some are lucky enough to be able to stay in the moment and not worry.
Ride on, everyone! Embrace the adventure!