Most of my adult life was spent in LE or the Military (or both at the same time).
All during that time, I played the "what if" games in my head. Every call I got, while responding it was "what if".
In walking down the jungle trail it was "what if".
Add to the What if, tons and tons of good solid practice will put you ahead of the game every time.
As to AVOIDING A FIGHT. Of course thats best. But you can avoid it without avoiding it.
I know that sounds like "Giant Shrimp", but think about it. You cannot avoid everything, every place. In LE you are sent to that place that should be avoided. In public CC, you can't avoid going to the ATM, you can't avoid stopping at a traffic light, you can't avoid setting home watching TV.
But you can avoid the confrontation in such areas. If you have good training, get some good solid practice, and play the "what if game" you're going to build confidence in your abilities to protect your self.
That confidence is going to be projected to others. Bandits pray on the weak, they will not go after one who projects confidence, who appears ready.
Take an experienced police officer. Spent his career on the street and has the experience and knowledge to deal with the street. Confidence is written all over his face and body language. Now compare the rookie, just turned loose from his FTO, he's going to be nervous and un-sure, the lack of confidence is going to be projected in his body language.
As a bad guy, ask your self which you would tackle and which you would avoid.
So you can avoid confrontations without having to live in a bubble.
Because you know I also strongly agree with you that just going over the pictures in your head does not buy you the physical skills you need to carry out your plan. Also, people who aren't well-practiced in those physical skills tend to have unrealistic ideas about what they will be able to do, and to make unrealistic plans based on that.