[Daryl]

Bernt, I don't know if this would make any difference to you, but the Book description of Low Point uses the Center of Gravity of the Clubhead, on the Sweetspot Plane, passing through the Impact Point and Low Point.

If we visualize Low Point in relation to the Bottom of the Clubhead Arc, then it may follow that Ball Separation at Low Point would have the Bottom of the Clubhead only brushing the Ground. It seems that Non-TGM people have adopted the term Low Point to define it this way.

But if we adopt HK's view as outlined in 2-N-0, and the COG of your Clubhead is 4 grooves up with a 9 Iron, you may take a decent Divot even if Ball Separation was at Low Point.

I'm doing some illustrations. So far they indicate that the Impact point, on the Ball is where it should be for a 9 Iron (That seems to be the "Given") and the Low Point along that Arc on the Sweetspot Plane, is about 1/4" above the Ground, which makes your 9 Iron dig about a 1/2" ( or a little less) Divot when Separation is at Low Point.

A lot of book info leads me to believe that Separation occurs before Low Point and that Low Point is directly below the Hinge (or should be in a normal and practical golf swing).

2-N-0 CLUBHEAD LINE OF FLIGHT The line of flight of the Clubhead and the Line of Flight of the ball are not the same but touch momentarily during Impact. The one has a vertical plane of action, the other an Inclined Plane. This involves the Angles of Approach (2-J-3) established by the Left-Shoulder-to-Ball relationship of the Lever Assemblies 1-L-11. This line cuts diagonally across the face of the Inclined Plane and passes through both the Impact Point and the Low Point. These points also locate parallel Plane Lines passing through them – that is, the Impact Plane Line and the Low Point Plane Line, each of which must use the “Sweet Spot” Plane (2-F). Herein, “Plane Line” means the Impact Plane Line and “Low Point” means Low Point Plane Line.