In Leafys back lat spread shot,his back is fully flexed and expanded, and most likely he cannot get it to flare out even one little bit more,but with hands on hips instead of in front, he would be creating an illusion of even more width because his elbows would be further away from his body,making him appear even wider than he truly is.
Illusion = real when you are seeing something like a pose.
That was a bit clearer explanation than my previous one I think.