[EdZ]

Could there be two "low points"?

There is a low point in the ground of course at the lowest point of the divot.

But there is also a low point in relation to the shoulder joint with regards to the #4 accumulator. Seems to me that once the left arm is directly opposite the left shoulder joint (the in line condition of #4) the left arm is no longer going down . . . but going up. So that would be the low point with regards to the arm swing but maybe not the ground's low point?

Keep in mind how you position the 'machine' may change where the club/ground contact occurs, but that is a different matter than the relationship of the hands (pressure points) to the rest of the machine.

Assuming the radius doesn't change and/or the center does not move (compensations) - every machine must produce identical alignments for a given result. The line of compression per 1-L.