A replica can never prove it holds every revocation. But merging is union and revocations are permanent, so withholding one can only delay it, and a single honest peer repairs the omission.

It is the trust story: what a malicious or lazy peer can and cannot do to you without a server.

No certificate can be judged alone. Only against a bag. And your bag might be missing something.

Miss a revocation, and you keep honouring access the full set has revoked. Until you sync. That is the window.

Can a dishonest peer keep you in that window forever? No. The moment any peer shows you the red note, it applies. And nothing can ever undo it.

One honest peer is enough. A withholder can delay. Never prevent.

The other direction exists too. If you never saw the note that made K an admin, you treat K's revocations as inert. Short on delegations means short on revocations. As notes arrive, coverage only grows.

Nobody can prove their bag is complete. Absence cannot be witnessed. What you get is weaker, and enough. You can be late. You can never be wrong in the open direction for good.

Check yourself. A peer hides a revocation from you. What bounds the damage?