I just realized that recent integration of G+ commenting was a big mistake; it locked out commenting (from what I could see) unless one is registered on G+. Typical of the great G(obbler)+. This may also be why I was not receiving notification directly from F.D. of certain visitors leaving comments on recent articles.
My apologies to everyone, and I have reverted the site to a more open standard, as it should be. Likewise, I am going to kill G+ based commenting on all of my managed sites on Blogger.