- shear_wave.fit_rate: finite late R=0 returns rate_fit_valid=false with null fit quantities (no clipping, no invented rate); own screens and budgets treat it as a failure (CONTROL_SCREEN_FAIL / refined FAIL), other finite metrics retained, JSON-safe. - test_projected_pairs: dry-run/execution mocks expect the explicit 'taylor_green' flow argument now passed to verify_source. - run_case: SHEAR_WAVE_SHA256 repinned; extinction test added. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>