Is this correct? For some reason, I have to get it into my own words to understand.
The upper torso must tilt and turn (pivot motion, right shoulder down plane) so that the #4 pressure point carries the #3 pressure point into release so that it can trace the plane line.
That's one reason (of many) that one cannot pull with the left arm only to start the downswing (a lot of topped shots).
It's just that I always thought the #3 pressure point is aiming from the top. Your explanation seems to work better.
The entire spine must tilt. The fact that pressure point 4 is working against the onplane pressure provided by extensor action means there is nothing else the body can do but tilt as pp4 is applied.
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