[O.B.Left]

Nice question. I've got a few factors for your consideration:

1. The loft of the club. Added loft itself will "leak". Intentional by design compression leakage. Although some backspin is necessary for flight. But we're talking theoretically I think. So theoretically shouldnt the direction the face points three dimensionally and the line of compression be one and the same for total compression.........which could imply negative loft in some instances?

2. Hinge Action. Horizontal is "closing only, no layback". Vertical is "layback only no closing". Angled is a bit of both depending upon the plane angle. As the angle approaches perfectly Vertical, Angled Hinging approaches the characteristics of Vertical Hinging (layback only no closing). Vice versa for the situation where the plane angle approaches Horizontal.....Angled Hinging approaches the characteristics of Horizontal Hinging (closing only with no layback). Which should probably make for a third factor ...

3. The Plane Angle.

4. How bout the Angle of Attack? That would cause the Line of Compression to be divergent from the target line wouldnt it?

5. Ball position vis a vis low point?

I dunno but my head hurts already. What does trackman say, Max? I hopped on a Flightscope the other day. Interesting but not enough info on that particular unit maybe. Either that or I didnt know where to look. The thing that really jumped out at me was how constant my swing speed was for different amounts of effort.......made me start swinging slower and better right away. My apologies for the digression.