> They could form a massive train ... with 1 inch of space between each vehicle. Okay, now a deer or a moose runs onto that road during a short gap in traffic.

> They could form a massive train ... with 1 inch of space between each vehicle. Okay, now a deer or a moose runs onto that road during a short gap in traffic. What happens next? > the more you look at self driving cars, the more they look like trains Sure, really big trains, with a tiny fraction of the carrying capacity.