OK, I have FOUND the problem, and it isn't W3-Total-Cache. At home, I only use Firefox to browse. At work, I have to use IE and once in a while, Chrome. So if I'm one one of those other browsers and want to check for new comments or something on the blog, I see the display, which did have Adsense working properly.
This morning when I got to work, I checked and indeed, everything is working fine in Chrome and IE. That told me that I had a local PC problem, which after further research, turned out to be Avast! I love Avast! for my firewall, anti-virus, etc., but it appears that they block ads automatically in Chrome and IE. While that is annoying, at least I know what is happening and why, which is a relief. I was really afraid my blogs were jacked up.