Good point. the WFC position illustrates it well. WEB hasn't sold much since the scandals popped up, but through investing in other positions, WFC's weight in the portfolio halved. However, implicit in my remark about private cars was that Geico could get battered at the same time. So these are two major revenue sources for BRK.
How do you reach this conclusion? If it works for short lags, why should it not be extended? Why not assume the opposite, that long routes might be the first where driverless will be deployed. That's where we see a shortfall of human drivers. It's a financially unrewarding job for the driver (train crews earn double their salary), with little sleep, and far away from home.
points 2&3 equally applied to cab drivers until 3-4 years ago. Changes are slow to come, but quick to materialise when they do eventually come. If big players find value opps, there could easily be a consolidation, just like in any other industry that develops technologically.
I know little about the industry but read that for the same volume, train cost is 100$ vs. trucking 130$ (though trucks have the door-to-door advantage). If the driverless convoy eliminates both fuel and personnel costs, a 30%-50% reduction in expenses seems reasonable, which means cost advantage can flip. With coal, its volume comprises about 18% of BNSF's freight revenues, so that's quite substantial. Yet on the other end BRK compensates for that through its MidAmerican Energy sub and clean energy initiatives.