Quite true, and in my opinion it is a flaw regarding the training purpose of the AAP. The F coefficient only reflects the consequence of the aiming trace speed at the breach instant, which has nothing to do with the aiming point. I think the 10a0 (as well as 9a0 and 10a5) percentage calculation should exclude the F coefficient altogether, and only the shot score should be affected by the F coeff.
In my experience you can have a kind of arm/wrist instability in which you can't really slow your moves but manage to control their amplitude better along the time, therefore increase your AAP scores. For instance I can hardly slow my small instability moves below 200 (in Scatt Expert) but with training my DA has already dropped from ~15 to around 10 or less, as well as the average size of my aiming zone. Consequently the F coefficient, which correctly simulates the actual score on the target, excessively affects the measurements of my averages.
As a result when I do exercises for stability training I have to set the F coefficient at 0, which allows me to compare these technical training sessions along time and measure my improvements. Then I set it back to the usual value of 10 for match training.
Where the (real) shot ends up on the target is a combination of where the firearm is pointing at the instant of firing and how the muzzle is moving, as this will impart a vector (combination of lateral and vertical) velocity onto the bullet/pellet which will 'throw' it in the direction the muzzle was moving by a distance that is proportional to the speed at which the muzzle was moving. The F-Coefficient/Ballistic Ratio is the proportion factor, and differs for each calibre of firearm.
The movement of the muzzle is a combination of how steady your hold and aim is, and how good your trigger release is (how much it disturbs your hold and aim).
By setting the F-Coefficient/Ballistic Ratio to zero, you are removing this 'throw', which means you are only measuring where your rifle/pistol was pointing at the moment you fired. In essence this only measures how accurately you 'see' a good sight picture (good enough to feel confident in releasing the shot). It is like shooting with a laser rather than a bullet/pellet, and is only half the story of how well you are shooting.
The 10a0 and 10a5 statistics are essentially the same as the 10.0 and 10.5 statistics, except that they remove the effect of your average aim point not being perfectly centred, either through incorrect zero or natural aiming errors (no shot is ever perfectly centred except by chance). 10a0 and 10a5 tell you how well you
could keep all your shots in the 10 or X ring
IF you could fire perfectly aimed shots and your zero was perfect. Even if you keep your trace inside a 10 ring sized area, you will not always get a 10 because of the 'throw' induced by muzzle movement - if the muzzle was moving towards the edge of the 10 ring zone at the moment you fire, you could end up 'throwing' the shot out and 10a0 recognises this in its calculation. Some people deliberately set their F-Coefficient/Ballistic Ratio to a high value, as they find this helps them to improve their hold, aim and trigger release during training (see other threads).
It is still possible to see performance over time through 10a0 and 10a5 whatever value the F-Coefficient/Ballistic Ratio is set to. The numbers will still reduce as your performance improves (indeed they will appear to reduce faster with a high value of F-Coefficient/Ballistic Ratio, so you will have a clearer indication of the rate of improvement).