Asymmetric Charge Covariance Does Not Protect the Equal Threshold
WP844 tests whether WP836's equal singular spectrum prevents the partial decoupling obstruction. At tree level (D=mH_q) gives (D^TD=m^2I). The allowed weak-basis-covariant hostile
changes the squared thresholds to (m^2+\epsilon,m^2+4\epsilon,m^2+9\epsilon). A centered, common-shift- insensitive charge square also splits the middle state from the endpoints.
Because (Q) has simple spectrum, its commutant is diagonal; the common commutant of (Q) and (H_q) is scalar. A quadratic correction (aI+bQ+cQ^2) preserves all three thresholds only when (b=c=0). Thus no currently retained source symmetry protects the degeneracy.
The required cancellation is the full traceless operator
whose squared norm is (98\epsilon^2/3). Deriving this cancellation needs a nonrenormalization theorem or additional source dynamics that leaves the asymmetric portal intact. Equal singular shape alone is a tree-level rigidifier, not threshold survival.
Verification: 12 of 12 exact checks pass in
research/flavor/checkers/wp844_asymmetric_charge_radiative_threshold_splitting.py.
Graph admission: ev-000000007919-2325139d-0699-4606-889d-84a659808b51.