Actually, UT Health Science Houston does have standards by which they allow people in their program.
I had a 96.6 on my HESI, a degree in biochemistry with a 3.92 GPA, and I almost didn't get in because they only have 1 (sometimes 2) people that verify your entire transcript, course by course. They were concerned that an alternative history course I had taken did not meat the requirements.
I received a rejection letter, proved that the course did meet the requirements, then received an invitation. Turns out I was #2 for my HESI. #1 was 1.4 ahead of me.
I never met a single student that had a low, near-80, HESI. I met a few with mid and upper 80 HESI's. Many had perfect 4.0 science/math pre-reqs.
80% is not competitive for UT, I promise.
After grades, HESI scores, are factored, they also look at demographics of the class. They won't tell you this if you visit them, but if you are fortunate enough to speak to one of the people manning a booth at one of their college sessions, you'll get a quick run down. Remember: the UT system is the last system in the state of Texas to apply race as a qualifier for entry. This isn't news, or shouldn't be, given the lawsuits of the previous years against UT, which have all failed.
An interesting note: during our information session, we were told males were given a slight preference. Perhaps the good doctor spoke too openly, or hypothetically, but I want to believe that may be true. My class had 10% males, and the class after me about 14% male.
Finally: Brace yourself for starting in the Summer- it's the most difficult experience ever. You'll be taking Physiology and Pharm at the same time, most students have a problem with that. The other courses are cake. Take heart, though, in knowing that your final semester will be in Summer, and all clinicals, crammed, but more relaxing, and you'll only have 1 exam to prepare for. Summer is the absolute worst.
My advice: study hard, learn to excel at labs (they offer open labs sometimes- practice makes perfect, don't waste the opportunity, or to practice skills with an audience, because you will be asked to do complete skill assessments later on, in front of everyone, solo). Make friends with Dr. Yu, and Dr. Hanaman (sp), and whatever instructor seems to take an interest in you. Instructors at UT, and being friendly with them can make an enormous difference in your experience.
Know that the group you start with will not be the group you end with. Your cohort will be whittled down further and further until, having passed through the most painful crucible, you stand with those who had the fortitude to get through it all. The UT experience is vastly different than the other schools in the area. It is far more difficult in many ways.