*   **Operation and Visible State:** The system must atomically commit the chosen revision `c`, the new operation `Q`, and the non-retryable status of `P` within a single recoverable transaction. This ensures that `P` is not reactivated after a restart if the process dies between transactions.

*   **Information and Policy Boundaries:** The scenario highlights a missing contract regarding the receiver's version and ancestry enforcement. Without this, the system cannot guarantee that an already transmitted `P` will be correctly handled by the receiver, even if marked non-retryable locally.

*   **Recovery Action and Rejected Alternative:** The proposed correction prevents `P` from becoming active again locally after a crash, addressing the risk of re-transmitting a superseded operation. The alternative of marking `P` non-retryable in a separate transaction is rejected due to the vulnerability to process death.

*   **Missing Contract:** The absence of a documented contract for the receiver's version/ancestry enforcement means the system cannot rely on the receiver to correctly handle `P` if it arrives after `Q` or `c`, or if it's a stale version. This requires external reconciliation or a defined receiver policy.