Meh...no big deal. During the early portion of the Wright Amendment, this would have been a big problem for SWA. These days, SWA can absorb a small decrease in DAL-Houston and not even see it on the balance sheet.
Why would people take a train that is twice as slow? Boeing gets me there in 47 minutes...the train, what, 2+20?
SWA can reduce the fare and people will still fly.
The Fed Guv will still require TSA screening to board the train...it just makes more sense to fly.