Talk about elusive and obvious at the same time.
I recently had one of those head fwap "I could have had a V-8" epiphanies. The fit of the riser & hand is critical to accurate shooting.
If the grip is comfortable and fits the hand, windage issues seem to dissapear and the more consistently accurate the shot is.
If it's too large or to small, you add torque/windage issues to the problem of alignment. You can make it work, but it's more work to do so.
Much like wingshooting, you can make about any shotgun work, but when you find the one that fits...