It appears the only point at which their trailing arms line up with the shaft is at impact and beyond. (perhaps startup)
This seems to be at odds with swings of the great hitters, and advise of just about every other instructor I can think of.
Are you saying that coming from inside is a power leak?
The Right Forearm can only be On Plane when the Right Elbow is On Plane. And, on the Downstroke, that occurs only during the Impact Interval (Release to Follow-Through).
Regarding "coming from the inside," Golf Stroke Geometry mandates that the Clubhead travel Down and Out to its Low Point (1-L-13). In other words, from the 'inside' toward the Plane Line (1-L-10) as directed by the Right Forearm and #3 Pressure Point.
I'll let Yoda give you the 411 on this new student.
Gerard, a 7-handicap, today left San Diego to pay me a visit in The Swamp. He has a fine Swinging Pattern with a very smooth, even Tempo. Lots to like. But, he had also reached a plateau from which there seemed to be no further progress, and he came looking for answers.
I met him in the parking lot, and after shaking hands, we spent the next half hour getting no further than ten feet from the trunk of my car. Hinge Machine, dowels, Impact Bag, Golf Clubs, Flail models...all were littering the ground around us. More than one passing motorist did a double-take, but I am pleased to report that The Golfing Machine came alive for Gerard this sunny afternoon down South.
His basic procedure through the Ball was to lean back and throw the Club past a bending Left Wrist. His Left Shoulder would move well back from its Address Location (essentially over his Left Foot) to approximately the middle of his Stance. Consequently, he was no longer in a position to drive down and through the Ball and was forced to 'sweep' everything. When he's 'on,' he can play. But when he's 'off,' the Ball can go anywhere. His Short Shot Pattern was identical, and he found it impossible to get that sharply accelerating, downward blow that is the hallmark of a truly fine Ball Striker.
By the end of our second hour together, all that had changed. The Ball was now located slightly further back in the Stance. His Head no longer Swayed back or Bobbed down. The excessive Downstroke Axis Tilt was gone. The Hands, instead of being in the middle of his Body at Impact, were now under his Left Shoulder and visually over his Left Foot (well in front of the Ball). The Clubshaft, instead of leaning backard through Impact was now leaning Forward. And at Low Point (opposite the Left Shoulder), it was In Line with the Left Forearm (instead of making a "Y" with the two Forearms).
The photo on the right was of an Acquired Motion Pitch (Right Forearm level to the ground on the Backstroke), hence the more narrow Stance. However, Gerard demonstrated the same action in his Total Motion (with a short Iron) as well. The Ball loved these new alignments and told us all about it:
Great combination of text and image really hitting home the point - it is so easy to slip back into an impact position shown on the left and wonder where the zip went. Explains a couple of poor shots today very nicely. Thanks for the simple reminder.
these on plane swings seem very upright compared to the shaft plane--aren't clubs designed to work from the shaft plane angle?? Does one need to adjust one's clubs to swing on the turned shoulder plane ??
the turned shoulder plane looks and is steeper than the shaft-elbow plane for which most clubs are designed--how much does one need to change the clubs lie angle ??
These on plane swings seem very upright compared to the shaft plane--aren't clubs designed to work from the shaft plane angle?? Does one need to adjust one's clubs to swing on the turned shoulder plane ??
The cambered sole with its rounded toe and heel permit the ready positioning of most Clubs between the Elbow and Shoulder Planes.