Just as the motion happens from the ground up in the transverse plane, it also happens from the core out. Michael Hebron called the phenomenon "the inside moves the outside" very correctly as well. The motion of the distal parts of the body should be subdued to the core action so that one could reach repeatability and consistency.
Post-secret Hogan had the most efficient motion ever seen. Leading with the rear elbow is biokinetically the most efficient method of achieving the EEP (because it subdues the elbow joint to the body rotation as quick as possible without taking away the inertial power of both forearms). But the elbow does not continue to move forward to the front of the body while extending the arm and stalling the body rotation.
What stalls is the joint exactly when the elbow plane is being achieved (very early) and put his rear forearm in line with lagged shaft. The stall (maybe is not the best word to describe the lack of further movement of the rear elbow joint but I cannot think about any better) is crucial. No independent arm motion in relation to the body rotation from that point. Perfect biokinetics. Imagine rear humerus being "tied" with the main body while the forearm supports the shaft. Nothing can be spoilt here.
Other mortals, who are not able to drive the rear elbow in so much a forward position so early simply are forced to move it somehow constantly and, therefore, are not blessed with such great body-arm-shaft synchro relationship. Nevertheless, it is still possible as we can see in Furyk's motion that everything happens also from the core out.
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