It's hard to say whether the long distance trains are viable as a transportation service, because they're also in the "land cruise" business and oddly enough that part seems even less profitable. It's the source of a lot of the expenses, especially for things like food service. Amtrak has actually tried cutting the diner on one of the Florida trains and dropping sleeper prices by $100, and is making considerably more money on that train, so there's still some potential to get close to 100% cost recovery on LD service if Amtrak gets out of running the land cruise business, which it seems reluctant to do because of tradition.