Gary Player said,
"Norman's swing has fewer moving parts than any swing I've seen." That is one of
the big secrets to Moe hitting the ball perfectly almost every single time.
You see, Moe’s swing (what he called “The Feeling of Greatness”) had less moving parts because he kept the club on a single plane.
Unlike traditional swings, the Single Plane Swing starts in the same position as the shaft ends up at impact.
Which means, less moving parts to the swing.
The extra movement caused by a two-plane swing (which is how traditional golf instructors teach you to swing the club) results in consistent inconsistency.
Moe instinctively developed a swing that removed all that extra motion and this "natural" swing was the key for his uncanny consistency.