We hit the streets of Mountain View at rush hour, and spent about 20 minutes navigating a winding route around the X campus. The speed limits never rose about 35 mph, and neither did our Lexus. X’s autonomous vehicles are Boy Scouts, meticulously following every posted sign and instruction. When lights turn green they wait about 1.5 seconds before proceeding into the intersection — a hedge against red-light runners. They seem to slow for stop signs roughly 300 feet before a human would.