FYI Same day prices are much much higher, buying a ticket leaving tomorrow from SJC->LAX is around $220, and SFO->LAX is basically sold out.
What's worse is that French, German and Dutch national rail operators have subsidiaries running rail contracts in the UK. So in a way we help fund the fantastic continental rail services...
But I understand that rail services on the continent are also heavily subsidised.
I'm in NYC and would never, ever fly to Boston or DC. For what that's worth.
1. I'm not sure how that affects my point.
2. In my experience the price difference for last minute on Amtrak has been at most about 20% (though I'm not a frequent Amtrak traveler).