The real problem, I agree, is that if you are unaware that it's a shared account, you might give access to notmyfandom_kinkmeme_mod, thinking it's your friend. That's a problem anyway with the shared password model, but I absolutely agree, there's a risk of people thinking a shared journal belongs solely to their friend, when in fact it has several primaries.
To be honest, shared journals are probably not going to make the cut for version 1, for this and other reasons.
Re: Shared access = massive security hole
To be honest, shared journals are probably not going to make the cut for version 1, for this and other reasons.