09-10-2010, 05:40 PM
I, and most instructors, have used various methods to provide feedback to the student about the movement of their arm. Some examples are holding their elbow in position, resting an item on the students upper arm with the goal of it not falling, and video.
What is really nice about the Stroke Groover is that the instructor does not have to participate mechanically, and the student can simply focus on the feedback from the Stroke Groover. Once they understand their stroking error, and how to correctly move their arm, they can continue to work on the issue on their own.
It can be used without an instructor, but an instructor can identify the errors and provide accurate corrections, and significantly shorten the time necessary to correct the stroke.