Exact feasible-witness controls
20/20 known-answer controls pass; state: complete.
All 51 coordinates remain. Twenty exact repairs and objective checks cover box, halfspace, boundary-anchor and point domains. An LP proposal is not presumed feasible. Invalid anchors are rejected; repairs use exact rational mixing.
The calculation performs zero LP proposals, native integration, aircraft reads or observed fits. A feasible point in a linear relaxation need not represent a physical calibration. The saved-region diagnostic is a separate study.