Does your statement assume the Left Shoulder's Adjusted Address location? If so, would "opposite the Left Shoulder at Impact Fix" satisfactorily locate Low Point?
I referenced low point and the fact that from Impact to Low Point the shoulder location moves upwards significantly enough to effect the low point and move it backwards slightly.
So No and No...lol
Opposite the left shoulder is the lowest point in relation to the left shoulder itself but not the lowest point in the clubhead orbit which occurs just prior to that.