I think we would lose a lot by restricting access to registered users. You never know who will drop in as a guest to provide some specific bit of expertise on a topic they know very well -- sometimes it's quite wonderful to see who has been lurking out there and is willing to contribute from time to time.

But every silver lining has its cloud. IMO it's not too bad a problem; just don't click on any spam links, PM Joe or a clone about the threads where spam appears, they will delete it, and it seems to me the problem is solved. The Spam can be reduced to just being irritating, not particularly dangerous or important, just "down in the noise" as the engineers used to say (maybe they still do).

Rita F