"Hm-m-m... Maybe a person could switch to a new computer, and re-register under a different 'handle'; then post merrily away as a new person."
A person need not even change computer! He or she can simply "log out" and then "log in" again, this time as an entirely different user.
I believe all that is required is an email address to register an account... If one person has ten email addresses, for instance, then it is clearly possible for them to post under ten different CureZone identities. Plus, if they were to post under each CureZone moniker and each anonymous number, then all of a sudden they have twenty identities!