[YodasLuke]

I can understand that you could be tracing the alternate plane line, but as I remember Homer specifically refers to the clubhead covering the alternate plane line and he usually meant what he wrote. I didn't see how the clubhead could ever cover any plane line except maybe if the club was on a completely vertical plane.

You're certainly on the right track. I've spent many hours studying this very subject.

I had problems reconciling the logical arguments and statements about this subject. My major concerns were with the seeming contradictions with 1-L. So, I knew I was treading in unchartered territory.

The Angle of Approach Procedure is a 10-5-E, closed Plane Line. This Plane Line is a line that is VISUALLY covered by the clubhead blur. The reason that the clubhead can VISUALLY cover and still move in a circle, per 1-L #9 is: the steepness of the plane.

When you're riding a bike and you look down at the tire, you see the straight line that the tire covers (wheel track). When you're watching someone ride beside you, you're seeing the side of the wheel (wheel rim). It's all about VISUAL perspective.

When Impact and Low Point are kept as two constant points on a 10-5-A Plane, a second Plane could pass through the same two points and be much more vertical. As the steepness of the new Plane approaches the steepness of the eyes (compared to the Turned Shoulder Plane with the eyes above it), it appears to be a straight line blur of the clubhead.

It's something that can be shown in a couple of minutes with two circles. But, it's a little hard to put into words.