Power comes from the release of the stretch that was developed by the SnF loading process. And that comes from two body parts working against each other in rag wring fashion to create the snap.
THE SNAP (POWER) COMES BEFORE THE HIPS EVER MOVE. The movement of the hips is simply the follow through....that happens AFTER the power release. The hip movement is not the cause....it is the effect.
Take some cuts with the idea of NEVER LETTING YOUR REAR HEEL LEAVE THE GROUND....and watch your suddenness and power increase. It will move despite your effort to not let it move....but that effort to not let it move is where the power comes from.

When you stretch a band around a corner wall and let go, it flies off with exponential force. More force than if it wasn't 'bent' around the corner.
The corner didn't move at all. Neither do the hips....until AFTER the power has been generated and released. Hip movement is simply a follow through action....NOT a power generator.
The STRETCH is the load. (a stretch against a RESISTING hip....not a moving hip). The release of the stretch is the power. The hip movement that occurs as a result of the release of the stretch is simply follow through.
You've got a ways to go before you start giving advice.
take a bat, plant your feet square to home and swing without letting them move...see how far the ball flies....
your welcome, glad to clear that up for you...
and I'll take my poor reading comprehension over this voodoo rubber band physics
"When you stretch a band around a corner wall and let go, it flies off with exponential force. More force than if it wasn't 'bent' around the corner." What is the exponent in this exponential force (here is a clue it is 1). F=kx holds whether it is around a corner, straight, upside down, with a goat, in a boat....you get the point.
I'll say again....having the feet planted square to home plate and not allowing them to move will restrict the hips from getting through and this will cause a batter to not be able to hit a ball as hard.
You will always push the barrel.
You will never whip the barrel.
Because.....you are PUSHING your hip instead of SnF'ing about the rear leg.
The hip must RESIST movement.
It is an absolute fact not dependent on your understanding.