He tells how he picked his percentage range right in the video, and he didn’t cherry pick his route, he picked a route that would take him from where he lives (Idaho I think) to Jay Leno’s; the locations of charging stations are tracked by the car.
I retract that he had to use 250KWH V3 superchargers. After reviewing 150KWH V2 charging figures they match up with what he said. If he would have had access to V3 superchargers the whole route, it would have been able to cut down his charging times by ~40%. Still, he either cherry picked his travel time or got incredibly lucky the V2 stalls were mostly empty along the way.