nothing to explain how he'll pull off developing a new technology and build it for 1/10th the cost of using established technology. except he's not going to himself, he's presenting a plan for others to follow.
he's a smart guy who got one project very, very right so has the cash to persue very, very expensive projects. i havent followed SpaceX, but Tesla is great but has some substantial problems not least hemorrhaging money.
a bit like how this Hyperloop, its sounds great but seems a little far...