Also when talking about fighting with the gun there is a line of thought that suggests speeding up until your groups open up a bit. Your all A zone hits while beautiful and fast could be A & B zones hits even faster while still being effective.
In a competition I would whole heartedly agree with you and I know for a fact that the top competitors give up A-zone hits in exchange for speed.
In a real life or death situation, given the relatively puny nature of handgun rounds and what it actually takes to incapacitate someone. My opinion is that the more well directed the shots are at the sternum and brain the better your odds are of success.