You got that right!!
Roger. Look at some of the videos you have and you'll see that, by the time the front foot has landed, the back foot has "rolled over" almost entirely onto the laces. This roll over happens very late though.
Rotating as early as shown in the photo is just plain wrong. It ain't rocket science. Nothing complicated or technical here, just that there's no contribution to the throw. It's that simple.
Yes, hip/shoulder separation is a key component in velo production but it's existence alone doesn't mean anything. Nothing. The most important thing is the effectiveness of the kinetic chain. The engagement of one component of the chain MUST happen at the point where the velocity of the preceding component is at it's maximum. The timing of this transfer is CRUCIAL. If it's ONE then PAUSE, then TWO, you've lost the opportunity to transfer the maximum amount of the built up momentum. You've also lost the opportunity to take advantage of the stretch shortening cycle of the involved muscles.
Look at the pros. The "chain" of events isn't really discernable when viewed at full speed. It's an extremely smooth, flowing transfer up. It's why they're pros. They just got it baby. They take all of these little, nit-picky details we argue about for years and put them together seamlessly. Efficiently. Effectively. That's the holy grail guys.