As I was growing up there were huge numbers of overloaded coal trucks and these trucks were tearing up the blacktop that had been laid down at considerable $ over the mountain gravel roads.

My grandfather and father were definitely in the “good roads” camp and further understood that overloaded coal trucks also wore out their tires “way before their expected tread wear life”.

It is “penny wise and pound foolish” to increase your $/ton by getting horrible tire life and then also pay more $/hour to drivers who have to slow down on torn up roads.

A similar thing can happen on a railroad if you overload railcars but in that case you destroy the rock roadbed below the steel rails and cross ties. This happened when they foolishly went from 70 ton to 100 ton railcars. Even worse the 100 ton railcars were too tall and unstable. One turned over and killed a friend of mine.

Caterpillar used to run free “Equipment Schools” where one section was how to calculate maximum load on those HUGE haulback truck rubber tires.

CAT believed that most operators were getting less than 50% tire life. Here load and speed both contribute to internal rubber temperature, which has a sharp upper limit. Drive just 2 MPH faster and the tire self destructs.

Robot driven huge haul trucks have a “hidden advantage” that you can command a robot to never exceed a speed that human driver “Joe B. Yahoo” ignores.

My father also was a big believer that every house should have been wired for 3 Phase electrical power, and that 400 HZ 3 phase has many advantages, as the US Air Force found.