If Low-Point is the Lowest Reached Point of Clubhead Travel (relative to the ground) before the Clubhead travels Up and Back, then Divot Length and Depth would relate to Ball Location for the pre-Low-Point Divot. Hand Location will be a determining factor in Divot Depth and Length as well as the Clubhead Travel from Level to Uncocked Left Wrist.
question #2;
What is the "shape" of the divot, on the ground, relative to the plane line?
HB
Hitters would have a Straight Divot down the Angle of Approach. Swingers would have a curved Divot down the Arc of Approach.
They may both look straight but much depends on the degree of Angle of Approach. In all cases the Divot should be relatively Flat and Wide. Depth is mostly determined at Set-up. Which Groove do you want to strike the Ball with?
Straight plane line and square clubace are required for both hitter and swinger the divots would have to be the same no?
I think D is talking about the Angle of Approach, an inside out, cross line procedure employed almost exclusively by Hitters vs the ARc of Approach Procedure employed by both Hitters and Swingers.
So to answer your question precisely.......Hitters are not "required" to use the Square Plane LIne, they do have the option of the cross line Angle of Approach Procedure (for balls played back of low point). They use the Square Plane Line to establish the Angle of Approach and then let the original plane line "vanish". We need drawings again.
If you're a Hitter dont worry about things ........the ARc if fine. Square Plane line Down and Out to Low Point then Up and In. Situation normal. Divots too Id imagine.....not 100% sure.
Speaking of divots .........how about Aiming Point vs Tracing, divot wise? Mine might be fractionally deeper with Aiming Point. Is that normal?