Yesterday, we published the first part of The rail theory of everything: a plan to make billions for the state, cut emissions, improve health, create nice places — and fix the housing crisis for good. The basic idea is that it’s easier to build a city around a high-performing transit network than it is to build a high-performing transit network around an existing city. So that’s what we should do. Building around a rail network has some big advantages. It scales, so you can house ten or hundreds of thousands of people in relatively few locations. It results in high…