Questions about particular use cases (integrity verification w/o private key, add E flag to primary key, import secp256k1 key)

[Robert J. Hansen]

> I thought you could also tell how many keys it was encrypted to, from
> the output of gpg --list-packets.

Nope.  You can tell how many subkeys it was encrypted for, but not how
many distinct certificates those represent.  If one recipient has 10
subkeys and you encrypt to all 10, there will be 10 packets awaiting
you... but there's no way to determine these all correspond to one
certificate.