What "that" are you referring to? In all the versions of GPG I've tried, 1.4,
2.0, 2.1 including this current one in git, it is possible to create a
Certify-only master key by toggling off "Sign" (and "Encrypt", for RSA).
I am saying this should be possible for the "=flags" syntax as well. I would be
happy with either "=" or "=c". The latter is clearer, but inconsistent with the
existing syntax in git which ignores "c" completely, and just forces Certify on
for the master key and off for the subkey.
$ gpg2 --full-gen-key --expert
[..]
Please select what kind of key you want:
[..]
Your selection? 8
Possible actions for a RSA key: Sign Certify Encrypt Authenticate
Current allowed actions: Sign Certify Encrypt
[..]
Your selection? s
Possible actions for a RSA key: Sign Certify Encrypt Authenticate
Current allowed actions: Certify Encrypt
[..]
Your selection? e
Possible actions for a RSA key: Sign Certify Encrypt Authenticate
Current allowed actions: Certify
[..]
Your selection? q
[..]
GnuPG needs to construct a user ID to identify your key.
Real name: Testing
Email address: lol@test
Comment:
[..]
gpg: key 0822FCC2D521C45C marked as ultimately trusted
public and secret key created and signed.
[..]
$ gpg2 --edit-key lol@test
[..]
Secret key is available.
pub rsa1024/0822FCC2D521C45C
[ultimate] (1). Testing <lol@test>
gpg>