I disagree with the pattern plate theory as a shot string on a moving target is a 3 dimensional shape whereas the pattern plate is two dimensional. If one is shooting at a standing turkey then that pattern plate will definitely show what your hit on a turkey head/neck will be. The only thing the pattern plate will truly tell you is POI if you have a consistent mount.

Outside of checking for POI on a gun, I never pattern anything but a turkey gun for that static shot.
I'll bet if Harry shoots 7/8 oz loads he'll still post his 96/100.