Oh sorry, I'm wasn't intentionally arguing against being pseudonymous. I was thinking of ways to manage the mutability, multi-mapped and non-uniqueness of common names behind the scenes. If circles can be kept separate, you could have a single login containing different circles for your pseudonyms. As an aside, I hate how current FB and G+ policy turns us non-celebrities into second class citizens. Disgusting.

Thanks to nradov above for info on HL7. Surely these major international orgs should already have been aware of it?