> We used to dig up roads to put trains underneath – cheaply. Ever-better tunnel boring machines have made the disruption this causes unnecessary. What? Sure,

> We used to dig up roads to put trains underneath – cheaply. Ever-better tunnel boring machines have made the disruption this causes unnecessary. What? Sure, tunneling machines make less disruption but unnecessary? You still have to build the stations, entrances, and venting systems. All of those breach the surface and the space needed to facilitate the construction still causes lots of disruption. But yes, more public transportation please. Lots of it!