O.k. I am scared and intimidated by tgm talk. I know only its more rudimentary terms. My problem, I tend to suck the club back inside, getting no separation between the hands, arms, and pivot. I like the simplicity of the big muscle theory but I am tired of dropkicking my drives.
Sooo, I am interested in the swing where theclubshaft goes back on the plane, then above parallel the elbow stays against the plane, but the clubshaft goes to a higher plane. Then in transition the clubshaft returns to the shaft plane. Why? you ask. The feel to me is one of height and lifting the arms higher than where they normally go. I am short and stocky and I feel like it will help me get some separation between the 3 zones. I promise I can swing the club through any part of the air and space around me. I just need to know where to go.....
Your description sounds a little like what I had experienced.
I was doing the back stroke using the shoulders and got inside.
Cure for me was..
1. Line the rt Forearm up with the clubshaft at address
2. Trace the Plane Line (line on ground that extends backward from the botton of the Inclined Plane).
3. Tracing is done by right action, not shoulder action
4. Apply right arm extensor action
5. If a Hitting stroke is to be done, the then a one smooth rotation to the top, if swinging is to be done, rotation should be completed by time hands and club are hip high.
6. If I am hitting my hands finish at the top at right shoulder level, if I am swinging my hands finish a bit higher. (Hitting is a flatter plane, Swinging is a bit steeper).
7. From here is is a matter of using the correct delivery path/line to get the club back to the ball.
Sounds simple when I read it, wish it was that easy for this old body.
Now all of this was to accomplish a zero shift.
You have described a double shift, first shifting during the back stroke from the elbow plane to the shoulder turn plane and then returning to the elbow plane on the down stroke. John Dunginan advocates this method. You can get some tips on his site about how he iniitates the down stroke.
Martee has given some great advice there, and even with zero shift it might still solve your stated problems. With your build (short and stocky) and pivot problems and all a hitting stroke with it's Right Forearm Pickup action might just be the saviour. Certainly no excessive shoulder turn or lack of separation in that motion!! Yoda is on the move at the moment but is going to try to ease on a bit if he can.
Just a quick thought, because I had trouble with driver dropkicks. (you didn't mention anything about iron chunks.) Make sure you are not losing your wedge and bend in your right wrist. It throws the arc off. My problems were because the ball was up on a tee, and I had ancient artifacts left over of lowering the hitting shoulder and tilting the spine to do it. These were junk left over from the "hitting up" with the driver delusion. Good luck.