We know that self driving cars will not solve all the world&#x27;s problems, but one can reasonably expect there to be some improvement. Whether that improvement suffices for a satisfactory level of service is another matter and will depend upon the reciprocal interaction between demand and capacity - which the article does not go into. But there&#x27;s no such thing as a panacea to free movement, whether you like the current form of public transport or not. Even if we got Star Trek&#x27;s transporters I&#x27;m sure there would be complaints about the congestion in transporter room five.<p>There are significant costs to public transport that the article hasn&#x27;t addressed as well. The switching costs of using public transport, whether you stay with the same form of public transport or not, are significant. The time you spend waiting for connections; the time spent waiting for all the other people to board, and alight, at their connections; the bother of finding which platform your train is going to be on when under time pressures to make the connection; the incredible cost paid when a bus, or train, is overloaded or unavailable.<p>It&#x27;s all very well to observe that a train can carry a particular number of passengers per mile per hour on a particular space of track, refer to the maximum theoretical capability of the system when trains are running within a certain safety distance. If you look at figures for energy costs, then public transport will similarly come out as the vastly superior option. But the cost of a form of transport is assessed in more than simply its use of space to move people through or its translation of energy into passenger miles.<p>Even when one is going to be stuck in traffic, it&#x27;s often more reliable, faster, and certainly less bother, to drive to the destination. Especially since the bus is going to be sitting in traffic anyway, that&#x27;s a tragedy of the commons problem going on there but it doesn&#x27;t change the underlying trade-off. For some that trade-off is so great that when denied access to private transport they can&#x27;t make the trips at all - I know people who don&#x27;t own cars, who cannot work 10 miles away, because the buses don&#x27;t run that early in the morning, or because there is one bus that runs that early in the morning and if it&#x27;s unreliable they&#x27;ve taken on a financial liability in gaining the job that they&#x27;ll be unable to effectively discharge because they&#x27;ll lose their job.<p>None of which is to say that public transport is a bad idea. I love the idea of fast regular trains that are little bother to get on, despite the fact that most of the time I drive to work. But if one&#x27;s in favour of it, perhaps it would be better to be in favour of it - in favour of improving it - rather than against something else.