The peep also works in a way like a lens. If you are familiar with pin hole cameras you'll get the idea. The smaller the hole in the peep the sharper the front sight will look. The Merit sights that fit the standard peep sight threads of Williams, lyman, Redfield and so on allows a very small hole or a larger ghost ring type sight. T/C peep sights can be fitted with with different apertures. A tiny hole near the eye will make the front sight really sharp.
The Skinner sight mounted forward in place of the open rear sight will not function as a lens and does nothing to help with the front sight. It really is not much more than a buck horn sight fully closed at the top.
I always tell people I've helped learn to shoot with a peep sight, many soldiers an some civilians, to think of the peep as being like a knot hole in a fence and behind that fence is a beautiful girl, of legal age of course, sun bathing in the nude, and you stop and check her out by looking through the knot hole. What are you focused on, the knot hole or the girl? Do you even notice the knot hole? The peep sight is the knot hole the front sight is the girl. Checking her out by standing out in the street and trying to see the girl through the knot hole just doesn't work well. Using a forward mounted peep is like standing in the street.