Binding: the Ruling

A bound neutron is still udd. The orientation is intact; nothing in the nuclear well touches the flip. The ruling, spoken and standing: the distinction is held against the structural alternative; binding closes the exit, not the window. The ε is a structural residue, not a dynamical option — availability in the ledger is structural, and reachability is the exit's business. The bound neutron pays. Its stability needs no second mechanism: the release is blocked (for the deuteron, energetically — there is no bound diproton; Pauli blocking proper does the work in larger nuclei), and a blocked exit over an open window is a hold that sheds forever, which the family already knows how to say.

Proposition (the capture-chain identity). The gamma plus recoil in n + p → d + γ equals the free neutron's booking plus the proton's minus the deuteron's, identically, by energy conservation, whatever happens inside. Therefore the tabulated neutron mass is the free booking always; the frozen row of section 6 tests the free neutron regardless of this ruling; an independent free-neutron mass would match the table either way; and a closed window's 2.7 eV would hide inside the deuteron's binding bookkeeping — B_d = 2,224,566.362 ± 0.373 eV from the CODATA-2022 mass triplet — where theory is a thousand times too coarse to look.

Declared plainly, because honesty counts edges rather than collecting them: this ruling carries no mass-face observable, under either answer. No switch is armed on it because no measurement can reach it. The only conceivable future handle is dynamics — the lifetime physics of the window's snap — and that is forward-register, held open in section 0.7.