I don't follow you here - see the highlighted area above. From what I could see in your pictures, the A plate guard isn't shortened, but it is lengthened. What am I missing?Using that nomenclature the shave plane for starters differs. The A plate has a steeper plane and since it is the guard that is shortened not the cap it translates to less blade edge exposed past that plane on the lower side which is where the cut starts. That also changes the blade angle from the standard plate i.e. the angle between the blade and where it passes the shave plane. It is apples to oranges here, if it was apples to apples then guards would have to be the same length. With that the only difference is the gap not 3 factors like now.