Personally, I always felt it was an impractical thought experiment you’d have in high school physics class after a lesson on friction and not much more. It was a great way to derail (heh) legitimate conversations about California building a realistic and cost effective high speed rail when it was first proposed.

Side note: Nitter still exists?! I thought they gave up

Why build a dangerous underground railroad for cars when you can just build safe regular high speed rail? Oh right, one discourages the overproduction and overuse of personal vehicles.