> Let’s say you want to provide an alternative to flying between some major airports. This seems like first-order analysis: people fly between SFO and LA so le

> Let’s say you want to provide an alternative to flying between some major airports. This seems like first-order analysis: people fly between SFO and LA so let's build a railway between them. Second-order analysis: people actually want to go from downtown SF to downtown LA, so build a railway between those places directly.