In this example the E slice with the red edge pair also has a yellow edge. This means that the sequence only separates the red edges into different slices, the yellow ones end up with a pair in the E slice. Hence the reason that it is preferable to not have an edge matching the color pair in the other slice. If both color pairs have matching edges in the other slice then this sequence is of no benefit but fortunately for those cases there is always another setup that can be made where at least one slice does not have this issue.