.... that actually trains offer a better service for personal transport ( between cities certainly...).
I can imagine an expert system of trains, buses and taxis could, even in a free market, develop into a cheaper alternative to owning a car for the cast majority of journeys - if only people *wanted* it that way. They dont, they dont like being controlled by a timetable and having to share seats with strangers. Cars are not the most efficient forms of transport, they are generally favoured for other reasons a huge one being provacy and individuality. Ones ford escort may be the same as the next one but your cassette is different, your furry dice are different and no one is sitting next to you unless invited - and most of all its yours, its not a temporary shifting from one faceless transport organisations seat to the next exposed to whomever else comes aboard whether you want it or not.
Its not about whats the most efficient. Im pretty sure a clever group could work out how to feed the world if only those darned humans would agree with it all!