As I mentioned in this post from September, I believed Gmail was ignoring the "dots" in email addresses. Believe I've found PROOF as of today. I kept getting emails from "Payless Shoe Source", a store I haven't set foot in since the early 1980's, once I found out how crappy their shoes are. So, I decided, instead of marking the emails as "Junk", I'd try the "Unsubscribe" link in the email. The unsubscribe link had a "dot" in the email address. My Gmail address HAS NO DOT!
As I've said before, I'll NEVER use Gmail for anything IMPORTANT. Their system is entirely screwed up!