[rayiner]

A change in one constraint might allow you to move to a different point in the design space, but it doesn't change the physics by which the system must abide.

More concretely, replacing a human driver with an automated one isn't going to change all the physical constraints that make it inefficient to have cars that cruise at 100+ mph: http://energy-ecology.blogspot.com/2010/05/optimal-vehicle-s.... Whether you're in a Honda Civic or a Ford Explorer, doubling speed from 90 kph to 180 kph triples fuel consumption.

Even if self-driving cars can be a little lighter, that's not going to change the shape of the curve.

[waterlesscloud]

Drafting, which results from the "car trains" I mentioned to start with, does change the curve. Dramatically. On the order of 50% decreases.

And that's with current designs.

Optimize your cars to maximize drafting effects and you can see greater improvements.