One other reference to blur does concern me though. It is in the last paragraph of 8-0 : "Then be sure you actually see the proper Blur of the Clubhead passage through Release." (6th Edition)
Could you explain what is the "proper" (or improper) blur?
The proper Clubhead Blur is a Three-Dimensional Arc -- Downward, Outward and Forward -- through the inside-aft quadrant of the Ball (from Impact Point to Low Point). The Blur (the Visual Equivalent of the Straight Plane Line) appears to the player as on the ground -- the Arc of Approach(In-to-Out). It is actually on the face of the Inclined Plane -- the Arc of Attack(Down and In-to-Out).