alt Hacker NewsTraffic lights can be tuned to create "green waves" that allows for efficient flow of traffic along arteries through a city. You can adjust the timing throughout the day to help alleviate congestion. In rural areas, heavy machinery/commercial vehicles may need to make a very wide turn through the intersection. Traffic circles are fine for a lot of applications but they aren't strictly better than lights in all circumstances.
I don't see how that could possibly be true. The same flow has to be achieved either way, and lights will always have some margin of inefficiency in switching. Seems lights will always be strictly worse than roundabouts in this sense.
There are also solutions for large vehicles where the center is raised but not impassible.