GnuPG can “disable” keys in a user’s keyring. This is not honoured by p≡p. p≡p instead implements it’s own blacklist.

In particular this means that when a user disables some key (with another GnuPG frontend or directly), for instance because the private part of that key was deleted, pep will still encrypt to that key. To stop this p≡p users have to blacklist the key or remove it from the keyring.