Originally Posted by Helmet Head
Technically, it is illegal to open a door without first making sure it's safe to do so.
If you're going to count on drivers actually doing this (not to mention kids in back seats opening driver-side rear doors), you're insane.
Some people have implied or even explicitly claimed that sometimes it's impossible to avoid riding in the door zone. I don't understand this. What could possibly prevent you from merging left? It's not like parked cars suddenly appear out of nowhere right next to you. If you believe that sometimes it's unavoidable, you will inevitably end up riding in door zones.
If you understand that it is never acceptable to ride in door zones, you will find a way to avoid them, always. Works for me...
I ride in door zones as little as possible. It's much easier in Manhattan where the traffic moves slower. In Brooklyn however it's a great way to have bottles thrown at you, cars swerve at you, or to have someone get out and simply beat your ass. I'm sure San Diego is a bicycling paradise where everyone respects you. When a car doing ~60-70mph in a 25mph zone tries to buzz you... you adjust.