Interesting, and makes sense to me at least in theory. I went back to check, and found I had remembered a bit differently than what I read...here's what Yardly has to say in "Gunfitting":
Pitch is usually downwards in modern guns (positive pitch, however, is frequently seen in muzzleloaders and nuetral or positive pitch in some trap guns). With a gun set up for game shooting or sporting clays, an average pitch-down measurement for a SxS would be about 4 degrees or 2 inches, and a little more, 5-6 degrees or 2.5-3 inches for an O/U. Less pitch than this may, practically speaking, make a gun shoot high, because pitch affects the way the gun is mounted.
It seems to be saying essentially the same as others here have detailed, but although I did not find it just now he does go on to say that others who have tested this have not found that it makes much difference, especially with a premounted gun.
Would different styles of shooting cause one person to be more susceptible to being affected by pitch than another?
