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Daryl,
The hips and shoulders turn perpendicular to the spine.
Tilting or dropping the right shoulders has no impact at all on creating ground forces.
Another myth is creating tilting of hips and shoulders. The reason they tilt is they are reacting to the spine, Tilting is a reaction to how the spine is moving.
In golf there is slight right lateral bending of the spine. This occurs to allow the right arm drive down into impact. Slight right lateral bending stabilizes at impact and extension of the upper body occurs at impact.

Regards Hogan,
Hogan talked about he fires his hips first, although was he aware his hips fired first, was he aware how this occurred. Golfers speak about how they feel their body moves although are they aware how this occurs.
Hogan had great lower body mechanics, Hogan knew how to create ground forces which created hip rotational speed for him and stabilizing his lower body at impact.
If you pay close attention you will notice from the beginning of Hogans downswing to impact his left knee maintains the same flexion. Hogan stabilized his lower body at impact and his hips decelerated. This allowed his upper body to close.
At impact notice Hogan sternum and belt buckle are in line this indicates. His shoulders and hip are square. His hips and shoulders are perpendicular to his spine.
Hogan has good movement patterns.

Hogan secret was in the dirt for sure he has wonderful lower body mechanics.
This was Hogans secret he knew how to create ground forces and knew how to stabilize his lower body at impact.

It's not about how big of a hip rotation you have, It's about how fast your can create speed before your lower body stabilizes at impact. Small rotation with fast acceleration is the key.
Which can reach peak speed fastest a huge hip rotation or a small hip rotation.

One other myth is trying to thrust your hips or turn them yourself. This is called superficial speed. When people try this they lack ground forces and can't create stabilization or deceleration of the hips at impact. The upper body can't catch up.Mechanics terms creates the over the top move. Everything spins out left.