That MacDonald exercise 4 is a distortion because she is standing erect. If the she performed that same pivot maneuver while bending over 40 degrees, she would develop a reverse K posture - because the degree of rightwards torso tilt increases slightly more with each degree of forward bending.
She? Heck, Jeff, we can't even agree on gender. I think a closer look will convince you of the fact that this is a 'he' and not a 'she'. [Short hair and no boobs are two of the more obvious clues.] If still confused, please see the remaining ten exercises here: http://lynnblakegolf.com/forum/showthread.php?t=4435.
And trust me, the Hogan Backstroke Pivot is a model for the MacDonald Pivot.
Head position, degree of Hip and Shoulder Turns, the Flat Backstroke Right Shoulder Turn, Knee and Foot Action . . . it's all there. The Pivot illustrated in the 'Guardsman' drill is a distortion of the Standard Pivot as defined (7-12) and illustrated (9-1 and 10-12-A #1) in The Golfing Machine.
I strongly suggest you adopt the MacDonald / TGM model and leave the 'guard' duty to others.
MacDonald's is simple - and guess what? It works! Golly, I spent my entire life examining 1000's of women and Mr MacDonald doesn't resemble any of my former patients. I wonder!