I think the professor's analysis by analogy to Acela is a helpful base. If CA's ridership projections are 10x higher than what actually happens in others' experience, and their ticket price was grossly understated, then the project looks deeply flawed.

There are clearly problems with the Acela analogy, but they cut both ways. For instance the CA trains would be designed to go faster [and derail if there is a tremor?]. But also East Coasters are more apt to take trains in the first place, whereas in CA trains are for everyone else to take so you can drive more. And, like Acela, you can just imagine what costs will be discovered down the line that noone anticipated...

I'd rather see CA pay down some debt than build the line.