I am curious about your third requirement -- "weapon is oriented on the target (sights on)."
Once you have decided to shoot and are in the process, do you let your finger leave register naturally as part of the firing process, or do you consciously delay your finger leaving register until the pistol has stopped and the sights are aligned? I can see the answer being different depending upon whether there is a non-threat there as well. The reason I ask, is keeping your finger in hard register until the gun has stopped and sights are aligned will add significant time.