In that case, it explains the mystery of why these seemingly harmless posts appear: I believe the forum software prevents brand new users from posting links (a crude spam prevention measure). So, the perpetrator posts one or more random blocks of text, then goes back later, once they have the ability, and adds the spammy link.
What a pain in the ass. Unless one has total recall of every discussion, this means we have to check to see if the same post from a different user exists already.
