St. Louis always seemed relatively normal or tame compared to other places. Chicago and now LA are just horrible.
I live near Chicago, and despite my astonishment of aggressive drivers, I'm used to local traffic. Highway traffic generally moves at a good pace, with the exception of rush hour. It's just that people think that the left lane is for doing more than 75mph (speed limit is 55), so if you're doing 75 in the left lane
and passing traffic, people trying to do 95 in the left lane get mad because you're not passing traffic fast enough. Traffic jams are awful though, crawling along for miles on end.
I just spent 4 days in St. Louis for work and had to commute 5 miles from the hotel to the office on the highway. There were very few backups, and if there were, they cleared up in 5 minutes. But there were a ton of assholes racing up the entrance lanes to the highway and then trying to cut into traffic at the last second.