Rick,
Having a car is a "nice to have," no question about it, but probably not essential. You'll be in a different hotel than anybody from previous classes (except January), but the Renaissance has a good reputation, so I'd assume that they won't have any problems with transportation either, just like the others didn't. Everybody rides in a van or two in the morning to class & in the afternoon back from class (even guys with cars, frequently). For the sims, you & your partner arrange for the van out, & then call when you're ready to be picked up. Lunch during the day is at the GO, so no problem there.
The time when having a car becomes a good thing is in the evenings & on weekends if you feel like getting out for a while. At least a few people in your class will have cars in Dallas, so going out with the gang to dinner isn't a big deal, but if you think you might like to go run errands or hit a mall or just go for a drive by yourself for a while, having your own wheels does come in handy.
I would concur with your buddy that having a car there, while not essential, is definitely a "nice to have" thing in training.
Snoopy