While I do agree that's excessive note that he's referring to what I believe to be (I've never actually been on the road) a very straight, flat, desert (no trees for wildlife to pop out from behind) road without a lot of traffic. Fly by other vehicles, I care. Fly down empty road, I don't care. (I'd like to see the speed laws changed--lower the penalty for speeding, increase the penalty for speeding involving a high overtake velocity.)
It is, and it was. Speed laws if they existed were not enforced. If you had a 200 mph super car there are miles and miles where you could “safely” come close to maxing out. (It is where they set the world land speed records)
Plus, it was well into nighttime for most of that trip.* Hardly anyone on the road.
I vividly remember the feeling of having to slow down 2-3 times in little towns … 25 mph felt like I could get out of the car and walk backwards faster!
Also, the biggest meteor I ever saw lit up the sky. It broke up into pieces and disappeared over the western horizon. Very memorable.
* the only mod on the car was its headlights, which I converted to halogens on day one because of the road I lived on. Nice at 115!