(Edit: I can be clearer, using your approach - more verbose explanation trimmed) In the linked version we are doing ... move, draw, de-overlap, move, draw, de

(Edit: I can be clearer, using your approach - more verbose explanation trimmed) In the linked version we are doing ... move, draw, de-overlap, move, draw, de-overlap ... So the move might cause an overlap, which we'd draw on screen. Having objects routinely interpenetrating a little (by a frame's worth) can appear springy, as if they aren't made of rigid material. Better would be ... move, de-overlap, draw, move, de-overlap, draw ...