The shoulder only stroke and the arm only stroke. There is no other mechanical stroke which stands up to them. A left arm stroke could be classified, so also a wrist only stroke, as well as a blend of any of the above four. BLENDING is not MENDING so I would stay away from taking any of the two and combining them.
The arm only stroke uses a push or putt basic stroke and the right elbow acts as a piston WHILE the right forefinger traces a straight plane line. The shoulders can move because they are considered a part of the power package as well as the pivot, however it is best to keep them steady as possible. Here the right arm will continue to push, straighten, and trace all the way to BOTH ARMS ARE STRAIGHT. This would have the putter head traveling down/out/and/forward to the low point oppo0site the left shoulder.
The shoulder only stroke utilizes the turning of the shoulders on an incline plane. As with all strokes the hands educate the pivot so tracing a staight plane line, moving the putter head along a plane board (angle) or using a curved device (putting arc) will teach the shoulders to move on an incline plane. The right shoulder must move on plane to keep the putter head moving on plane during the shoulder only stroke.
The shoulder only stroke moves the Thorasic Spinal region, not the lumbar or cerebral. Therefore the low point of the shoulder only stroke would be opposite the Thorasic Region of the spine which is slightly further back than that of the left shoulder.
So low point for the shoulder only stroke and low point for the right arm stroke are different.