Ah, I think we've been talking past each other. The typical view of HSR is that it is viable for HSR journeys of four hours or less — not that it is viable for

Ah, I think we've been talking past each other. The typical view of HSR is that it is viable for HSR journeys of four hours or less — not that it is viable for car journeys of four hours or less. This means SF–LA should be well within the viable HSR distance (per above, it really shouldn't take more than three hours by HSR).