AFAIK, the Germans don't actually use Maglev, just high-speed steel-on-steel rail systems. They're slightly slower than France or Japan as well, but their network is more "connected" (i.e. multiple routes between cities) as a price of that, and also, train frequencies are good compared to other European countries.

Actually, Dallas to Houston is only about 240 miles. You don't even need true high-speed rail to be competitive. A medium-speed electric train averaging 100 to 120 mph would beat the socks off of car travel.

You'd need a decent network of commuter trains at both ends and/or car rentals that can be hourly as well as daily or weekly.