I did not suggest that ALL posts from posters with the guest prefix be ignored and it is of course more complicated. I am more than happy for someone else to attempt to explain it clearly.
BUT
If you received conventional mail that is unsigned or phone calls from folk who do not identify themselves, for pure and varied reasons. You may very well not automatically ignore them? However you would probably be, sensibly wary? …..For that is what I am suggesting.
Max chose the word guest, after careful thought I am sure. For it does bring out in most of us, an almost automatic charitable reaction and one which we have quite a struggle to fight against, when the prefix is abused.