His numbers aren't "wrong" but he uses max COA, which for most schools is intentionally overkill (they must cast a wide net for a reasonable living for all students, including students with families with kids leasing absolutely everything).
I think his main point is that the tuition the schools post on their website should not be what you should expect to pay. He is absolutely correct here. Increase TUITION by about 25% (we did this down at the TMDSAS thread for the TX schools) over the 4 years and you can probably take down your living expenses quite a bit. Most cities, you can get a rinky dink apt, a couple roommates, cook at home, carpool/public transportation, and all that jazz and it'll really help you from digging yourself any deeper than you need.
Personally, I'm going to be living with mom and dad, eating at home, and driving 30 min to school each way. My only luxury is going to be a nice gym membership so I don't go crazy or get fat.
However, he says UTHSCSA will cost ~300k, but when I was doing some serious research thinking I would need to find my own place and calculating all that jazz with tuition increases and everything, I got to around 250k. So that's knocking off 50k for one of the cheaper schools. I'm sure you could easily knock 100k off his estimate for some of the more expensive schools if you live reasonably.