This is what I see in the ‘behind view’ video. Putting your mouse pointer on the tailbone (try no to over do it
) – at transition that tailbone does not move forward. If the hips were sliding it would. Because the hips are turning back towards the target, from a turned position, there is some ‘arc’ of forward to make that turn. I think the ‘slide-illusion’ referred to in an earlier post is a front-view-phenomena. Without the tailbone anchor reference the rotation appears to be a slide as visually things are moving from right to left (for righties). But if that tailbone is not going towards the target – you are not sliding.
How bout them apples!