[Brit]

This has been a very nice exchange of ideas, and a lot of experienced Instructors use historical data to validate their training methods, a good valid path.

Physics dictate results really. The pistol, weight and ergonomics, plus the holster, in terms of removing this object (a gun) from it's resting place, concealed on your body, It is hard to time this exercise in a gun fight! Other factors are on your mind!
But we can test this action on a range,an electronic timer works.

Knowing that when a bullet leaves the muzzle, it's trajectory will be in an ever widening path, till it hits something, or some body.

The fastest way to achieve hits is to go as close to a straight line as possible, from holster to trigger press, so up lift pistol till it clears forward lip of holster (good idea to have a lowered lip, a cut away) at this time the pistol is pointed at it's destination, and punched straight at the target, if going to a two handed hold, that second hand is contacted, during that line following, gripped tightly, and helps in the forward trajectory of the pistol, the shot breaks at the end of that stroke, or close to that point.

The distance from muzzle to target dictates that target. Rough numbers follow, 6ft, nose, 15ft upper central chest.

And remember the rule, the quickest time /distance, from A to B, is a straight line. Less than 6ft, your hands move quicker going forward, than down to your belt and back. So grabbing a gun and going hands on might be the way to go, burying a thumb into an eye socket with one hand, whilst your other hand keeps the muzzle of your assailants weapon away from your body comes to mind, your choice.