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The checklist posted is what Homer Kelley used and suggested to use with a golfer's golf swing.
3Jack - I agree with all the posts here - except for your quote above- certainly a common misconception - Homer Kelley didn't use that as his pattern and didn't suggest that you use it. It's a sample pattern - and that's the approach for most on this forum- not to put people in a box- but work with "their pattern". However, I'll give you credit in that his sentence in that section "Avoid "customizing" it with other Variations until it approaches the "expert" stage." is really horrific advice and appears to support your post.
Since he wrote his book to categorize any and every stroke possible - you have to keep that in mind. So, while this pattern is a full swing pattern- and the zero shift is not applicable- the zero shift certainly could be applicable for short shots - putts, chips etc. However, I understand that mostly "we" are talking about / thinking - full swings.
Finally, you'd need to be careful about not recommending a zero shift to a student and suggesting or commenting on the plane shifting - it would be easy for someone to think that they would consciously need to shift or feel a shift. The correct perspective for a plane shift would be from the 3rd person perspective - visually through the camera lens/video. From the 1st person perspective - procedurally - a zero shift "effort" is an excellent approach.
Anyway - a couple of nuances to the fact that a zero shift full swing - ain't happening on full swings.