As seen in Elon Musk’s attempts to reinvent transport. I’ve already posted a takedown of Hyperloop, so here’s one on the Boring Company.
tl;dr
In short, Musk,
a) has little understanding of the drivers of tunneling costs,
b) promises reducing tunneling costs by a factor of 10, a feat that he himself has no chance to achieve, and
c) is unaware that the cost reduction he promises, relative to American construction costs, has already been achieved in a number of countries.
