Shooting at an angled target will show wider groups when looked at straight on.
When viewed from the same angle as they were shot, the groups will be tighter.
Just plain old high school geometry.
Ok, so we won't sweat the root cellar, anymore.
Of course you could avoid all the criticisms by using a target on a stand, well to the right of the shack.
But then what would we have to complain about.
But do check out the reverse Weaver grip.
It's kept me going past my sell by date.