I've thought a bit about roads and it seems to me that having 2-way streets is a poor choice at the highest level. When you're driving north, the LAST direction

I've thought a bit about roads and it seems to me that having 2-way streets is a poor choice at the highest level. When you're driving north, the LAST direction you'd want to go is south. Yet the closest thing to you at all times is the southbound lanes. To go west - which you want to do more than go south - you have to cross those lanes. As soon as you decide to make all the roads one-way, a whole set of other issues come up, but having to stop and wait for half of your turns goes away. The EPA drive cycle for city driving has an average speed of ~20mph and that turns out to be close to what I experience even when posted speed limits are 45mph. Traffic lights are a plague, and IMHO traffic circles are not much better. All I can say with certainty is that it's complicated.