Im starting the chimp zombie movement.
I used to not even have a gun. I didn't like guns. Then on a very sunny Sunday afternoon, I went to the grocery store intending to buy kitty litter. As I exited the car a young hispanic man approached me, gun drawn, pointed to the gun to my head and demanded my car keys.
I actually stopped thinking.
I am not like you. For one thing, I am meaner than old dinosaur bones so I fought with him. It was completely instinctive. We fought until the key ring broke and he got the key. You will do whatever you would instinctively do and no amount of planning will change that. If you really are PLANNING to go all zombie chimp, I hope you are already training for it so that zombie chimp will be your instinctive, trained, reaction. Otherwise, you will just pee your pants.
Now I carry all the time. I won't take the dog for a walk without snuffy in my pocket. It is actually safer because had the jacker's gun gone off in the struggle, not only could I have been killed, but anyone in the parking lot was at risk as well as people across the street. Had I a gun, I would have just taken him out right away.