Actually John, it appears to me that the slot may have a slight slant upward to the front. So regardless of the direction of the slant, it could have some adjustment for elevation, albeit not much. I would be more inclined to think that the slot was cut deeper to the rear to provide bit more "beef" to strengthen the cut, and windage/elevation adjustment (if any) would be incorporated in the sight insert. Nothing like taking a few WAGs when all else fails!
