I should like to include some information to modify the postulate, or more precisely the idea that it "always applies" "has never been refuted" and is "universally applicable". No offense, HankT. I just think others should have complete information on something so important. Hesitation over incomplete information, erroneously thinking they may not shoot,may get someone hurt or killed:
...Review the above. Six women. Four rapes prevented. Six very possible murders prevented. Four dead attackers, and two crippled for life as a result of their own vicious misadventure. Only one of these six women criminally charged, and she, finally acquitted. There are lessons here.
Note, for example, that four of these six women were ruled justifiable in shooting their attackers even though the men they shot turned out to be unarmed. The principle is called “disparity of force.” The law understands that when a male violently attacks a female, even with just his bare hands, the likelihood of him inflicting death or crippling injury is so great that she is justified in using a lethal weapon against him in self-defense. (emphasis added). --Massad Ayoob
Although I cannot provide a cite, I recall reading that an old man against a much younger, stronger man fits the definition of disparity of force.
Also, Massad Ayoob, in his video Judicious Use of Deadly Force talks about:
Being knocked down and being kicked, the issue being that you cannot roll with the blows the way you can when standing. He tells the class he will show them photos of people who died that way later in the week. Justified lethal force.
And, an unarmedintruder coming towards you to take your gun away from you. Justified lethal force if the other elements of AOJ are present and there is no requirement to retreat, or if there is, the defender has run out of room to retreat.
You have a nice idea, HankT. And a way of presenting it such that it makesan impression. Why not present it the way the rest of the self-defense world does? The principle of Disparity of Force. Disparity of force tends to admit the broader subject material.