[12 piece bucket]

Great post Mathew!
I've looked up Tettsui Uchi and it appears to be concerned with the red dot section on the left hand. How does this red dot relate to the flat inclined plane?
Using the compass/dial, when does it make contact? When does it cease contact?

Remember for the club to be on plane . . . a simple check is to SEE if it is pointing at the Plane Line . . . that would include the butt in which is the heel of the hand. If you actually go through this exercise the butt end points well downplane on the back and through stroke. Laser from pp3 but also out da butt.