Is that seriously it? Like people looking out the window? I spent 4 years in LA traffic and have never heard of that. It's definitely plausible though, now that I think of it.
Lived there for a decade, and recall a time that we literally turned off our cars and met random people in the jam. I think it was during the trend of people jumping off of overpasses. There's also the random attractive person that cuts you off, flips the bird, etc. you just can't get out of your mind.
I got punched by a guy at a stop light in Atlanta. Practically the same thing.
Context: I yelled at him for trying to turn left at the wrong time. He caught up to me a couple lights later, walked down the median and popped me through my open window, then ran away. I hadn't said anything bad, just "I have a green light," but I think he misinterpreted my pointing.
