That article does bring up an interesting point: the degree of violence you are facing. At what point do you need to pull a gun?
Most threads here discuss scenarios in which you are presented with no doubt that a gun is the best option. I would be willing to bet, however, that in reality, there is going to be a lot more ambiguity...
These are the types of situations I know that I need to spend more time thinking about. If someone breaks into my house at 3am with a lead pipe, I know I'm going to shoot him. No debate.A gun will fend off any enemy. But what if the enemy is someone you know? What if they are intoxicated, or in a state of mind that, under different circumstances, they wouldn't normally try to cause you bodily harm? You'd want to defend yourself, but not kill them.
If a homeless guy walks up to me on the street and starts hassling me, maybe gets in my space or gives me a push, what do I do then? That's not worth drawing a gun, is it? What if he suddenly reaches into his pocket?
What if you come out of the theater with your family and find someone leaning against your car, or following you to your car? Does either of those things make you draw a gun? How much more threat do you need to perceive before you will draw your gun?
It's the escalation of a situation from seemingly harmless toward something that could be harmful that should make you think. Any idiot knows you should draw and fire if a carjacker busts your window and sticks a knife in the car. The more subtle situations require a lot more forethought, or you could very quickly end up on the wrong side of the law (or worse, shoot someone you don't want to shoot, as in her example quoted above).