I do like Pappy, I round more judiciously on the back just so I don't pull too much of my back ring off.
In addition to preventing splinters, I think the outer edges of a limb do less work than the wood nearer the center. So you are getting rid of less-working wood by rounding. There's something called the Poisson effect, its where the edges of a board curl up when you bend it. I'm not quite sure of what is going on here but I think it demonstrates that there are not equal forces acting across the limb.