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Comment by WalterBright | Hacker News Reader

Around here the power goes out to the lights now and then. Interestingly, the traffic flows smoother and faster without the lights! Even the arterials! It's amazing! Drivers simply politely cooperate with each other.

(The same thing happens when a traffic cop handles the intersection.)

I'm always assured that the city traffic light engineers know what they're doing and design the lights for maximum flow. They do no such thing. They are either incompetent or deliberately set things up to impede the flow of traffic.

Most of the lights now have cameras on them. Would it be so hard to connect them up to AI with the goal of "maximize throughput"? Imagine how much gas would be saved. It would be tremendous!

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At 4-way stops I find myself incredibly frustrated at the lack of roundabouts in the US since the traffic moves so much more slowly. But for high traffic intersections traffic lights are just more efficient since they let more cars through on average.

I think much of the issue is that by solving it at one intersection you simply move the problem to the next intersection. I'm pretty sure putting a roundabout at the 280/Page Mill Road intersection would improve throughput but nobody would get to work any quicker since the choke point is the next intersection along.

> Interestingly, the traffic flows smoother and faster without the lights!

I agree with that at off-peak times, but when lights malfunction at peak times, that seems to make traffic a lot worse.

Moving to the US, the traffic light system was a big culture shock for me. No major/minor dendritic road system laid out like a tree like I was used to — more like right angles everywhere and so many delays. Traffic lights on every single intersection. So inefficient.

And when you mention it, a surprising number of people say “that would never work here. People don’t know how to drive”. So little faith!

That's because traffic lines exist for safety not efficiency. They guarantee a time during which you can drive through the crossing without looking, while introducing idle time.

That's how the traffic in India actually works. No sudden moves, no surprises, no AI, everybody cooperates.

This has been found over and over, the more traffic control devices the worse the driving.

The Netherlands has it.

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