You're right in pointing out the ifs/thans of different types of intruders into your home, but the point of this string is what one type of gun should be bought that will cover all situations. If I were sitting in my bedroom, with my family safely behind me, and waiting for the cops to show up, I would love to have a shotgun. But a shotgun is a hazard if I have to leave the room. A handgun of the type I've described works in pretty much every situation.
Also, if you have the time and resources, get yourself a sheet of drywall, stand off about six to seven feet (the average engagement distance), and fire your shotgun at it. Let me know how many pellets you find stuck in the drywall or just on the other side. I'll save you the time and effort - the answer will be zero. At six to seven feet, even bird shot goes through drywall like butter. As for standing off 30 feet, most people can't standoff 1/2 of that distance in a typical house. You can also try standing on one side of some drywall and having a friend fire your shotgun at the other side. If you live, when you get out of the hospital you can tell us how many pellets they had to pull out of you.
As for my training being "unrealistic", my training is based on scenarios developed by reviewing about 7,500 actual incidents since the mid 1970s. If I add them to my training it's because they are a repeated trend seen in shooting incidents. As for the bad guys, you should consider that an intruder doesn't know your house like you do. When they are startled, they become confused as to where to go, and when lights start coming on, they'll start looking for places to move to or hide if they lose their escape route. There are cases of guys being cornered in rooms and just surrendering, cases of some rushing past homeowners and fleeing when the homeowner enters the room they are in, and cases where the bad guy uses a blitz attack to disarm the homeowner. The first two situations pose a minimal danger, but the third is very dangerous and often fatal, which is why it's in my training.
As for your contention of "
no intruder is going to be lying in wait for me after making enough noise to alert me of his/ their presence unless I come out of my bedroom hollering "Hey! Who's out there? Who's in my house? You better leave if you know what's good for you!!", you're right in about 82% of the case record, but that number's dropping as home invaders become a more prevalent threat. Burglars will leave in a hurry because they're usually unarmed, but home invaders are usually armed and more willing to challenge an armed homeowner.
No offense, but I get guys like you in my classes from time to time. You all have the same mindset, all think a shotgun or carbine is the best weapon to use, all think they got it down. Then I run them through a walkthrough and they find out how little they know. I have a gorgeous M-4 Carbine in my rack that I got from a guy just like you who bet me there was no way I would be able to subdue him. He lost.