Earlier quoted context omitted.
Related to this, take a look at how lobste.rs handles new members: you either need an invitation from an existing one (and your behaviour is associated with that person in the public tree of membership referrals) or you go into a member-visible queue until someone who knows you and is a member can invite you personally.
That's very clique-y.
Initially there is the bleeding edge, and then there is the long noisy end.