No sorry I have to disagree the height of the comb will not alter where the gun is pointing in any way. What you see from the change of comb height is what you are referring to. Think about it.... put the gun in a vice and then raise the comb the gun is still pointing in exactly the same place. It is no different when you put it to your shoulder it still points in the exact same place even when you move it everything in terms of the geometry of the gun and your shoulder is exactly the same BUT what you see is different because your head is in a different position. The gun is still pointing in exactly the same place though so to be able to hit the target you must change the point in time when you squeeze the trigger. This takse a bit of thought but the only thing changing is the position of your head the gun remains in exactly the same position. If the gun does not stay in the same position then you have not only changed the comb height but somehow or other the fit of the gun in your shoulder... which completely negates the idea of making small changes in comb height.
You are actually BOTH right. What differs is your view point and I suspect, the way you mount your gun.
If you raise the comb of the gun, you have made the gun taller. In order for you to mount the gun, either your face has to come up or the gun has to go down.
Back to your "gun in a vice"; you are of course correct, that clamping the stock and raising the comb, does not alter the position of the barrels.
But what if you clamp the comb, then adjust it? The gun moves, so the barrels point to a different spot.
So, if you as a Trap Shooter, pre-mount your gun to the same spot in your shoulder - raising the comb means your head has to come up and you get a higher view over the gun/rib, but the barrels still point the same.
If a Sporting Shooter shoots gun down AND mounts the gun to the face first, before it comes to the shoulder (kinda does both at once really, but the face, is the height stop), then the head does not move, the butt of the gun moves down and so the barrels POI has changed - but you still get a higher view over the gun/rib.
If the same Sporting Shooter mounts to the shoulder, then brings the head down...the result is the same as that of the Trap Shooter.
However, in both (probably any) case, you still have to have a sense of where the gun shoots.