Interesting. Tried to include some of this in my rounder line bump skiing - well, in the very limited time I got last July in Oz. The big difference to travelling straight down the fall line is more frequently meeting the bump from the side with more time between bumps. Dictated partly by terrain but mostly by age.
Wouldn't describe it as pulling feet back myself. It's back of heels travelling towards the glutes. A Big Picture Skiing vid suggested the cue of feeling like our butt is moving down perpendicular to the face of the bump. Because the front face of the bump is pushing the feet up the upper body doesn't drop at all - it just sort of feels like it. The legs fold in front but the upper body momentum brings it through over the slowing feet so they travel back to be in the right position cresting the bump. Works for me - less things to think about. Everyone's MMV.
Aside: there's a timing thing here. Pull the feet up early in anticipation of the bump and there's no real reduction of speed. Delay a fraction, allow the skis to meet the bump, partially resist the leg folding to prolong the initial merge with the bump and there's speed control. Look for a nice big bump face for extra speed control.
Glad you wrote that. A few people have observed that the OP sometimes extends too soon. In a rounder line there's good reasons to hold the flexed position to get the skis pointed in the right direction and edges ready to engage. Felt that was another key learning last time skiing. Eighteen months of squats helped.
^^^ very accurately described I would say. Nice writing!!