[YodasLuke]

A gyroscope built into a golf grip would do the trick to show the hands that plane.

Patent pending

If this post doesn't move the thread to the lab, I've done all I can do.

I was thinking more of the shape of a cone. Imagine a golfer standing in a Plane. Now, imagine the plane of the base of the cone is placed on the golfer's Plane, with it's vertex extended somewhere out and in front of the golfer's face (above Plane).

If the Sweet Spot traveled in a perfect circle, a machine could be built. Because of the true elliptical shape of the Sweet Spot travel on the Plane (not a perfect circle), it cannot be a right (triangle) cone with a constant length of "s" (slant). It would have to be an elliptical cone, and therefore would create many problems in designing a machine to hold the Sweet Spot On-Plane, acting as a Plane board substitute.

1. With "s" being of different lengths in this elliptical cone, a machine with a fixed vertex would have to have an "s" that telescopes in length. How would it know when to lengthen and shorten? If done incorrectly, you would add the third dimension to the plane (bad news/bending of the Plane).

2. If "s" was a fixed length, the vertex would have to telescope toward and away from the Plane. How would the vertex know when to move to or fro. Problems, problems, problems.

3. Or, use a plane board, and get the best representation of the Plane known to man.