> In DC, people carefully adhere to red lights, stop signs, pedestrians, etc but will go far, far out of their way to block you from changing lanes once they see your turn signal go on.

The last part, yes, but the first half has very much not been my experience here in DC. I usually see at least one driver blow a stop sign, red light, or one-way street before I make it 2 blocks from my house. The other thing I found amazing is that it's totally normed that you can just park in the traffic lane whenever you want — not just FedEx/Amazon but I've seen people park downtown at rush hour, get their dry cleaning, and get back in their car as if it was normal.

I think the main cause here is that we have a bunch of poorly-trained commuters from suburbs where they're used to high speed limits and wide, less used roads but the traffic means they're lucky to average 5mph on their commute into the city and a certain fraction of people cut any corner they can because they think they're owed a higher average speed. They're “running late” every day because they don't want to admit that their “30 minute commute” is off by a factor of 2-3. I'm curious whether the pandemic will lead to people trying to stay at 100% telework after realizing how much better life is without spending a couple hours a day stuck in traffic.

This would be a neat reinforcement learning project.

> Some places the drivers are so polite to the point it really makes things dangerous

I've known people like this, who will approach a 4-way intersection and stop even when they don't have a stop sign and the perpendicular street does.

Places where I've seen it, people who have the right of way take that to mean they get to play "traffic cop". E.g., at a 4-way stop the "extra polite" person who gets there first, instead of going through the intersection first, waits and waves the person who does not have the right of way to go through first, which makes that person (and everyone else) confused, and then causes a lot of slowdown, frustration, etc. Of course only happens in certain locales, where it's part of the local driving culture.

Or they slam on the brakes at the end of what should be a merging ramp or lane because the fore and aft distances to the other traffic that were good enough for the prior N people would be too close for them.

Well to be fair the distance most people feel fine with is not near what is safe.

this has always bothered me.

if you have the right of way, and you do not take the right of way, in most cases you are effectively disobeying traffic rules and disrupting the flow of traffic.

In rural areas where this is common there isn't traffic. Thus the politeness doesn't cost you anything. Also in those rural areas it is somewhat common for someone with the right away to have a reason to drive much slower than the speed limit and so giving up your right away makes things better for everyone - the other person doesn't have to try to pass you latter.

When there is traffic you giving up the right away is impolite to the person behind you and shouldn't be done. unless traffic is so heavy that you won't be able to move, and so you should give you your right away to someone who can go.

> Also in those rural areas it is somewhat common for someone with the right away to have a reason to drive much slower than the speed limit

Why does living in a rural area make someone more likely to have a reason to drive below the speed limit?

Because they often are farmers with equipment in tow that is instable at speed. 20mph (40kmh ?) Is too fast for a hay wagon.

> who will approach a 4-way intersection and stop even when they don't have a stop sign and the perpendicular street does

Not the main point but I never liked how traffic signs aren't affirmative sometimes. In the case of the 4-way usually the stopping direction have a stop sign with a missing "All Way" sign below it. But thats not required in all jurisdictions. Nor is the non-stopping direction 100% sure their stop sign is still visible (shrubs, weather, etc) and can proceed at regular speed.

I'm sure there are a ton of reasons for the way things are, I just think the outcome is you can't really ever be 100% sure what the correct thing to do is without slowing down and observing.

Speaking as someone who recently blew through a 4-way stop with other cars waiting, because the setting sun made it hard to see the stop sign, yeah, there are no shortage of human factors at play.

Stop signs are the shape they are so you can recognize them from the reverse for this purpose

Hard to recognize them from the reverse when they're hidden behind a bush!

Participating in traffic all comes down to being as predictable as possible, I think.

Yep. I prefer the driving rule, "Don't be nice, be predictable."

That is, don't deliberately be mean, but don't extend any courtesy where doing so would come at the cost of being predictable.

Yes, but in a way that's obvious to other drivers.

Driving decisively is more important to overall safety than driving defensively.

*and people on foot or bicycles

> Some places the drivers are so polite to the point it really makes things dangerous

I live in a small town that has extra polite drivers. It was really confusing for a while. Eventually I realized that it was a practical response to the overall street layout, with a limited number of main streets, and different areas of town not being well connected. Stopping to let others cross improves the overall traffic flow - if no one did it, traffic would just be backed up for miles.

> I'm really curious why some places...

Based on my experience of living in different countries, differences in behaviour and car culture are often underlined by hidden aspects of legislation which support those differences. I'm thinking more in terms of who is liable in the event of a crash, rather than the actual traffic rules.

>Some places the drivers are so polite to the point it really makes things dangerous

I think the danger you are talking about generally comes from the lack of anticipation and lack of meeting expectations, rather than the politeness.

If you shock a driver's expectations, that will at least appear dangerous, because they have to consciously react (or crash). A Bangkok-style driver in DC is dangerous, just as a DC-style driver in Bangkok is the dangerous one.

It would be cool to study things like politeness, top speed, acceleration, etc in different cities and then create traffic profiles that represent these cities and see what kind of tweaks can improve each one.