A case can be made for "better" patterns due to lower gas pressure at the muzzle, longer sighting radius, higher swing effort, but probably not being 6" closer to the target. Have they ever been proven? Nope!! Can they be proven? I doubt it. There is a problem in testing called signal to noise ratio. I'm willing to speculate that the signal to noise ration is just too low to sort out any differences at a cost anyone is likely to pay.

Unprovable theories make for interesting debates.

DDA