BJJ...I concur that if the sight has a rounded back end, like a polished barley-corn sight, you can get the light bulb effect from the side and that will through you off. But I agree 100% with Daryl, that the angled flat on the sight tip is all one sees, or what one sees most and first, when using this sight. If you are afraid of seeing sight blade below the angled tip, under cut the back of the blade so it is in shadow.
I usually make the angled top the same length as the sight blade is thick, so that it appears as a square of bright sight. For longer range shots, I just put this shiny square (that appears to be almost round to the eye) on top of the rear sight's horizontal plane, and in the centre of the target, and bingo...tack on.