So when people talk about a swinger using horizontal hinge action in their total motion, they are actually using dual horizontal hinge action.
That's right, kebeal. It is standard practice to eliminate the word Dual when referring to Dual Horizontal Hinge Action and Dual Vertical Hinge Action. Homer Kelley himself did the same thing.
How can this be done without compromising the precision that is the birthright of The Golfing Machine?
First, other than with Putting and short Chips, anything other than a Dual Hinge arrangement would be extremely rare. In fact, due to Club design and the necessity to stand on one side of the ball or the other, Horizontal Only and Vertical Only Hinge Action are virtually impossible to accomplish except in the short Strokes.
Second, when Horizontal Only Hinge Action (10-10-A) or Vertical Only Hinge Action (10-10-C) is used in the short shots, that specific terminology becomes the differentiation.
And remember, there is no Dual Angled Hinge Action, because the Clubface and the On Plane Clubshaft utilize the same Angled Hinge.