Sorry, I don't understand. Can you describe your use case in more detail?
Ah, scratch that, I think I got it.
The use case as I understand it occurs due to gnupg's way of binding token keys to specific keys in the keyring, which is an implementation detail. I suspect that any user that attempts to do something like this who is not a developer of openpgp software will only get burnt, and I don't see how that is worth losing the identity property of fingerprints in a keyring.