Interesting videos MechAge.
I didn't hear anything about the "choke" they were using on those shotguns. I also wonder why 2.75" shells vs. 3" loads.
I have an older Stevens SxS with a 3" #4 Buck (40 pellets) in the left barrel with a "skeet #1" choke (1 tighter than "cylinder") and a 3" OO Buck (15 pellets) with an "improved cyl." choke in the right barrel. As this gun has 2 triggers, it can produce a "cloud" of 55 pellets that should be effective, even if the intruder has body armor. As the late G. Gordon Liddy used to say on his radio show - "Body armor doesn't cover everything."
If I were to ever have to use that gun on an intruder, the two best points to hit are either the neck area (carotid artery and/or jugular vein) or the groin (femoral arteries) as they are less likely to be protected and the crotch can either take out the artery or break the thigh, putting them on the ground. The neck is the lesser target as the intruder can move his head and torso much more quickly than their legs.