Well, to be fair, the estimated average annual daily traffic for the most traveled LA freeways isn't anywhere near 100K per hour, either. It's around ~400K vehicles per day, and assuming 1.5 average riders per vehicle, that's 600K people. So if 200K riders per day is the most optimistic published ridership projection for CAHSR, it's not at all a bad number. (Acela's daily ridership appears to be closer to 30K, though, so I would be really surprised if the CA system is that high.)