It's a good question, Jim. Same one they suggest you ask yourself when you take the CCW training. When the time comes, and for me it's something I've yet to encounter, I imagine you really have to have it together. You can't blink when it comes time to react, yet at the same time you can't and shouldn't over react. Neutralize the situation if possible, but don't get caught napping and let them get the draw.
Also imagine some encounters would be blatantly obvious what to do, the attack would be on, while others might be more coy to begin. How to handle it?
I'm a jock, lots of sports competition in my life. A majorly important part of that was something called visualization. You mentally rehearse your performance before you actually compete, visualizing in your mind every movement you will be making in great detail, to the extent it almost feels like you're actually doing it for real. I can see the same exercise being valuable with this.