Lots of good advice here. I ride in LA, and read recently that it is legal to ride with one headphone (in my case, earbud) so I often do that.
The great thing about riding clear of the door zone is that you no longer have to scrutinize every parked car to see whether there is anyone in it--just stay where the door can't hit you if it opens and concentrate on cars that are actually moving. Lots of streets in Los Angeles are wide enough for bikes to ride out of the door zone and still leave room for cars to pass in the same lane, but if the lane you are in is not that wide then you need to ride far enough to the left that drivers can't think there is enough room to pass you.
Remember, if drivers get mad at you and honk and shout you know for sure they see you. If Angelenos see you they won't hit you--it messes up their cars and makes them late for Pilates.
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Inside of a dog it's too dark to read.