Well, User IDs are not easier to work with than User Attributes. The
only difference is that User IDs have been defined to be free-form
UTF-8, while the only User Attribute that has been defined (up to now)
is the picture type. And thus the only User Attribute that's easy to
work with is the picture User Attribute… which sounds logical.
OTOH, supposing my idea was introduced, then the additionally-defined
User Attributes would become mandatorily supported in v5 keys (among
other reasons because there would no longer be any User ID), and there
would be a free-form tag=value type (with both tag and value being UTF-8).
May I point you to the (expired) document,
draft-atkins-openpgp-device-certificates which started down the road of
adding additional Attribute packets.
Would something like that help?
Derek Atkins 617-623-3745
Computer and Internet Security Consultant
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