Have you ever been in Pittsburgh? I cannot fathom many cities have a worse network between the myriad of bridges, triangle shaped downtown and geography.
Driving in Boston is a nightmare... but you don't have to do it! Even if you're out in the suburbs you can park your car and ride the train in. LA doesn't afford you that option, really.
This is one of the unspoken rules of the road I learned on a trip to Puerto Rico, only it's not only at traffic signals -- any time a vehicle is signaling a left turn common practice is to slow/stop and allow it to make the turn.
No kidding! I recently visited Pittsburgh and remarked to my passenger that I'd have zero (expletive deleted) chance of getting anywhere on time without a nav. More than once, I missed turnoffs and entire roads when navigating the hills outside of downtown.