[tonyarkles]

> The same road surface would suddenly have 1/3 the throughput

At the same velocity. It's quite possible that with the increased gap and increased flow (less stop & go), you could get higher velocity out of it to compensate. Maybe not 3x the velocity, but 2x gap and 2x velocity seems within the realm of possibility (a 60mph road that slows down to 30mph because people are driving stupidly).

Edit: on the low end, this seems quite possible. Increased gaps raising the mean velocity from 5mph to 15 or 20mph.

[tonyarkles]

I'd edit again, but it's too late. This question kept nagging at me. I figured this must be a studied phenomenon.

https://en.wikipedia.org/wiki/Fundamental_diagram_of_traffic...

This is super interesting! As kind of expected, there's a middle zone that balances out density and velocity. In the context of what we were talking about, the fourth "Basic Statement" jumps out at me: "If one of the vehicles brakes in unstable flow regime the flow will collapse."