A comment from someone who makes a living out of relaying ribs is an answer to Stanton. It is from Art Isaacson, of Art's Gunshop..

"There are two kinds of ribs, those that came unstuck and those that will become unstuck".

For me, seeing the rust when ribs are lifted off, is enough to prove that side ribs (and bottom ribs on a SXS) do more harm than good. Top ribs are a pointing aid for many shooter and in any case, they do not create hidden rust traps.