The consequences of carelessness for AIWB carry can be greater than for other carry positions. I believe everyone would prefer a bullet in the butt, next to the hip or down a leg rather than in a femoral artery or one's maleness.
This man in the video failed to follow safe holstering rules in two ways:
1. He did not clear the path to the mouth of his holster. As I recall in the original video, which was much clearer and longer than the short clip in this thread, he had a t-shirt on under his polo. That t-shirt bunched up over the mouth of the holster, obstructing it.
2. Because he did not clear the path to the holster, when he pushed the gun into the holster, he pushed the t-shirt into the trigger guard. At this point in the original video, you can see him wiggle and force the gun because it didn't feel right. It was not all the way seated in the holster because of the t-shirt interfering. He should have stopped right then, his second chance to avoid injury, but he did not. He left the gun slightly out of the holster with the t-shirt already starting to pull the trigger.
When he bent over, he pushed the grip of the gun down into the holster just enough to finish pulling the trigger. The gun discharged because the trigger was pulled through his negligence. The gun did not go off by itself. There was no mechanical failure.
This kind of carelessness would have caused the gun to discharge if it was carried in any other position also. In fact, he might have had more of a chance of avoiding these two mistakes by carrying up front because of the potential ease of seeing the holster and feeling the obstruction.
In addition to being negligent with holstering safety rules, he apparently violated Cooper's Rule #2--Never let the muzzle cover anything you are not willing to destroy. "Never" is an absolute word connoting no exceptions.
I did not hear the extent of his injuries. It could have been anything from an uncomfortable muzzle blast to his privates as the bullet passed by to actual torn flesh and blood of a most serious type, although as he was treated it did not appear this was the case.
There are videos involving guns and holsters and people shooting themselves in all carry positions. There are even more reports with and without photos in the press. Then there are additional instances that we just don't know about because they are unreported.
The great thing about human intelligence is we can learn from others' mistakes and avoid them ourselves.
I made a statement earlier that a handgun put away safely into a good quality, modern holster that retains the gun and protects the trigger will not fire by itself. I believe this is true, even if a "safety" breaks, because modern guns have redundant safeties to avoid just such mishaps. Unless the trigger is pulled somehow while a gun is in a holster, it will not go off. If you carry a gun that you believe will go off after being safely holstered, get a different gun.
Get the gun into the holster safely, and no matter where you carry it will not fire until you manipulate the gun. Leave it alone and you are safe. The video above does nothing to detract from that statement.
No matter where you holster carry, you will muzzle yourself sometimes. Go to a class where people are using holsters and you will see muzzling happening all day. Think about your body. Could your leg or butt ever get down in front of an IWB 4 o'clock carry position? Do you have a roll of fat that pushes the grip of the gun away from you a little at times, pointing the muzzle in toward you?
So is the solution to perfect observance of Rule #2 not to carry? No. The solution is to carry safely, recognizing and minimizing the risks. Follow safe holstering rules in addition to the four basic safety rules, but understand that there are exceptions to the application of all rules that are situationally dependent.
My long guns in my safe at home are unloaded and pointed up. Rule #1 says treat them as if they are loaded. OK. On the floor directly above the safe is a toilet. The guns are pointing at the toilet. Rule #2 violation? Technically, yes. Practically, no. The guns will not fire themselves when stored in the safe, even if they were loaded.
My guns do not point at my flesh when I holster in any carry position, including AIWB. Once my gun is safe in my holster, I accept the fact that my gun firing in my holster (possibly while pointed at something important of mine) is so infinitesimally small as to not bother me. That's my choice, and I'm good with it.
I just seriously doubt that anyone who carries concealed can honestly say they have never violated Rule #2 while carrying.