However, one thing should be clear. It doesn't make sense for a manufacturer (or gun owner) to sight a pistol so that it hits significantly below point of aim at distances like 7 to 10 yards. It's become common for people to claim that certain guns are sighted this way, however not only has it not been my experience that such a thing is true, it doesn't make sense.
I would add that there is enough difference in velocity to change your trajectory slightly. my 9mm (115gr @ 1150fps) that hit roughly 2" above the sights at 25 yards will hit just under the top of the sight blade at 7 yards while my 45 (230gr @ 800fps) with the same 25 yard zero will hit right above the top of the front sight blade. It's a very small difference but it's there.