A deterministic Petz candidate and its certificate

No entropy or greybody statistic was substituted for $\zeta$, $ϵ$, or $r_{\mathrm{dec}}$. A recovery claim additionally needs the same-model preparation, complete evolution, access identification, and complement certificate emphasized in En07-B and Hawk04-D CheungEn07B,CheungHawk04D.

Whole-code recovery is also stronger than one-effect recovery. For example, qubit dephasing preserves the basis effect $|0⟩⟨0|$ exactly but has whole-code recovery error $1/2$. This is the kind of target separation documented in Oai290-A CheungOai290A. Finite streaming workspace obstructions belong to their specified benchmark and resource models, not to every possible decoder CheungEn02B,CheungEn02C.