X-G is not bypassed by formal quantum corrections

The supplied X-G material reports an obstruction to an exact source-preserving variational upgrade and the strictly positive classical witness

The symbols in this witness belong to the X-G data and hypotheses XG. They are not silently identified with the XVI-A preparation. The strict inequality is retained as a reported predecessor fact, not derived from unspecified assumptions on $M_{\chi }$, $\zeta$, or $\sigma$.

deduction. Corrections beginning at strictly positive formal powers of $\hslash$ cannot cancel this nonzero classical coefficient.

. For arbitrary formal coefficients $a_n$,

because its constant coefficient is $W_{\mathrm{XG}}\ne 0$. Equality of formal series is coefficientwise. This argument concerns formal corrections of order at least $\hslash$; it makes no assertion about numerical cancellation at a chosen nonzero numerical value of $\hslash$.

Changing the action may change the model or the hypotheses of the obstruction. Such a change is not a source-preserving upgrade of the original model merely because it is proposed later. XVI-A supplies neither a counterexample to X-G nor a proof of the excluded upgrade.