I agree. Most people think a gunfight/using deadly force is one fight. There are actually two more fights you will have to handle. Number 2 is the legal fight and number 3 is the emotional fight. You have to win all three and you should consider all three before you start fight number 1.
Ehhhh...
Do you really want these thoughts clouding your decision-making when it comes to a split-second decision of saving your life or someone else's?
When it comes to apprehending someone that's trying to get away... sure, I can see the thought process being there. Best to let them go, and assist the police with video evidence, etc...
When it comes to personal safety and self-defense... I think it's best to not think about those other things. Could cause a bad outcome.