Rewatching the GUY video, they really did a masterful job in slimming her down. I'm surprised I didn't notice it before, but they weren't lazy for most the scenes that required it. Best changes being the flower scene where she's wearing the white one-piece. If you notice, the flower background actually changes a bit so they can easily edit her waist without drawing too much attention to any obvious warp effects. The background actually changes depending on the way her body faces the camera. Profile view == bunches of smaller, white flower; Frontal == Regular background:
For some of the quicker cuts, they did still resort to the warping method. They also did the same for the dance sequence with her in the gold bikini, but it's more difficult to tell since there's a lot going on in the background and they keep her body shape consistent through each frame, which must have taken a ton of work. Nothing lazy like a Mariah or Xtina figure warp. Money was spent on her immaculate thinning.
For some of the quicker cuts, they did still resort to the warping method. They also did the same for the dance sequence with her in the gold bikini, but it's more difficult to tell since there's a lot going on in the background and they keep her body shape consistent through each frame, which must have taken a ton of work. Nothing lazy like a Mariah or Xtina figure warp. Money was spent on her immaculate thinning.