Only one problem with your scenario. In this case the officers already had their guns drawn and aimed at the individual. Reaction time to simply squeeze the trigger is almost zero.
If the man’s gun never came out of the holster they had absolutely no reason to kill him.
You are wrong. Don't believe me? Try this: http://getyourwebsitehere.com/jswb/rttest01.html
Keep in mind, this would be your reaction time, sitting safely behind a computer, WATCHING and waiting for the green light to appear. What's your best score?
If the man’s gun never came out of the holster they had absolutely no reason to kill him.
Absolutely wrong again, both from a physical threat perspective and from a legal standpoint. When you get a J.D. come back and talk to me about the law regarding the use of force.