Part of my commute takes me down a one way road that has diagonal parking on both sides of the street. If I leave work at five-ish, I often have to dodge morons who just back into traffic (not just bike traffic, they do it to cars and trucks too). Tonight, I had to dodge one car who didn't stop until I shouted at him, after I'd passed him while doging the car on the opposite side of the street, which was also backing up. After I was clear, they both backed into each other.

Did you stop or keep going?

Why would I stop? I wasn't involved, they didn't hit me. It's clearly not my fault that two drivers aren't paying enough attention reversing their vehicles into traffic. I didn't see anything, I just heard the crunch behind me. I don't know who hit whom, or if they hit each other. If one of them was having a heart attack, there was plenty of traffic they should have waited for to call them an ambulance.

I can think of many things that would be a better use of my time, but very few that would be a bigger waste.

Schadenfreude

when traveling down a road with angle-in parking (which i do almost daily), i am always on my guard. because it is so common to have a car back out into me when angled-in and not quite so common when straight-in, i just assume it is hard to see a bicyclist from their perspective. thank god for backup lights, and the fact that they don't back up real fast.

i sometimes wonder if the reason i like to ride in suburban and downtown traffic is that i have to be extra vigilant and alert.

Scream as loudly and as early as you can. Even with the windows up they can hear you. An air horn might help, but the reaction time to move your hand to the button is lousy compared to screaming. Nothing beats screaming.

LOL

I've been in a similar situation, stopped alongside diagonal parking. At some point I started slapping the sheet metal or window of cars in they get too close.

It has gotten me yelled at a few times, and an apology at least once. Either way it gets the attention of the driver very fast as it sounds like they hit something. As far as I'm concerned if I can reach the vehicle with my out stretched hand the car is too close anyway.

While you can scream at the motorist, if they are pulling out in front of you down the street a bit, you may just need to slow down or stop and let them out.

Kinda of if you were driving a car, would you honk and swerve around them or let me in?

exactly!