Comment by bobthepanda

the problem with the "car-like-a-train" thing is that trains have really high capacity because their crossings are managed and they do not decouple/couple at high frequencies, but more importantly the people to space ratio is significantly higher, particularly since standees take up very little room. when you consider that cars need a whole engine for four seated people the general end result is that "cars-like-a-train" combines the worst of both worlds.