Maybe I have had a change of heart:
If the Cantor's Kliros has general registered user access for posting, I figure I can read it, then private message anyone whom I would like to talk to further. Some cantor issues are delicate in nature, and not suitable for general discussion. A private forum would make such discussion easier, but the problem of identifying cantors still remains.
I see no way to definitively identify bonafide cantors versus wannabees, etc., within the church itself nowadays. Not all jurisdictions see cantors the same way, or have a way to recognize them. Not all jurisdictions have cantors for that matter.
I also see the administrator's idea of going private after a couple of weeks as a probably workable solution as well.