These are the faults that lie in this "experiment", faults that make the scenario vastly different than the one the show was supposedly trying to replicate:
1) None of the students had any firearms experience; they were chosen only after showing an "interest" in the subject, then shown pretty much only which end of the gun points away from you.
2) The guns were worn in basic, strapped holsters, not the kind that are used in tactical carry.
3) The holsters were placed in awkward, inappropriate locations on the belt.
4) The holsters were covered by markedly oversized T-shirts or other clothing, on which the guns frequently snagged.
5) The "madman" was not the cowardly, deranged subject that usually appears in real-life mass-shootings, but was, in fact, a law enforcement firearms instructor.
6) The "madman-instructor" was briefed beforehand in each scenario who to shoot at first (the teacher, then the "defender"), and exactly which student was the "defender", and where he/she would be seated (right in the middle.)
7) The scenarios were ended each time a "defender" took a hit, despite the fact that countless anecdotal evidence shows that a person fighting for their life can continue to do so in most circumstances even after being hit.
8) The scenarios were not necessarily ended when the "madman" took a hit, and credit was not given for it, since the "defender" usually took one as well. This assumes that any defender who is shot will drop right there, while any BG who is will soldier on. Truth it, these madmen are, in fact, cowards, and will fold and run (or commit suicide; more than 90 percent do) once faced with armed resistance.
9) In one of cases in which the "madman" took a hit, the shot came close to another student. The "defender" was criticized for the shot for endangering her fellow student but, in a real life scenario, if she withheld fire against someone bent on killing all, the other student, as well as herself, would be killed anyway. Against such an adversary, any defensive fire is worth the risk.
10) Every scenario assumed only one potential defender.
11) Bottom line is that most CC licenseholders would be far better prepared, equipped, and trained mentally, physically, and logistically, than any of the students that participated in this, and the deranged mass-shooter would not have the "advantages" afforded to him.
It doesn't take courage or bravery to enter a crowded school with two semi-automatic firearms and a couple hundred rounds of ammo, and proceed to open fire. Lawful concealed carry would change that.