ideal self-driving cars basically remove (b) from my equation. The thing is, even if self-driving cars are around the corner now, I reckon that the type you can

ideal self-driving cars basically remove (b) from my equation. The thing is, even if self-driving cars are around the corner now, I reckon that the type you can just leave on its own without any humans inside are still far out. Even just a solution for driving in bad weather conditions hasn't been tackled at all yet - you can't just shut down the city transport just because snow has covered up most of the visual markers. So, self-driving cars isn't going to solve any network problems for quite a while, and even when they do you still have overhead (a), which intuitively I'd say is even more important. I don't think it's that complicated btw. - if you do, please provide things I haven't considered and significantly change the outcome of the calculation.