A point that is brought up in the article is, "how is 8 shots self defense?" I see this question echoed in this thread more than a few times.
I've fired a real handgun before. My very first time, it was a 9mm glock with a friend of my dads. I thought, wow, this thing is cool. I'm going to drill that block of wood, and everyone is going to be so impressed (I was 12, I think). I emptied the whole clip (and hit nothing but dirt) before my dads friend could tell me to slow down. That was a 15 shot clip, and it was gone in a second.
The rational mind, the thing you're using here and now reading this thread, is not the same as the adrenaline saturated mind that you become drugged by in a dangerous situation. For anyone that's faced sudden and immediate danger, your mind panics. You don't make rational choices. You just act in a way that your instinct tells you to to save your ass. This goes for a kitchen fire, a mugging, a rape, a cave in, whatever.
It doesn't surprise me that after getting clocked in the face, Baker squeezed out 8 shots. He hit 4 times, and that was probably all luck, considering the lighting conditions and the blur effect of being punched. He feared for his life, and acted in panic to defend himself. 8 shots is the act of a panicked man.
Now, was he right to kill a man? Well I won't judge that. But at the same time, if it happens to me, it would probably go down the same way.