Don, great post... but a big problem. Very likely user error on my part, put here's what happened...
I went to the friendly URLs and made the changes per instructions, following along with the video. I thought I did it right, but clearly not. As soon as I hit save on the new rule, I was taken to the welcome page of my site (which is under construction and the homepage is set up with a "coming soon" screen for unauthorized users).
Now for the fun part: when I clicked on Login to get back into the site, I couldn't get to the Login screen! At all.
Clearly, I did something wrong. Hopefully I can figure out what that is as soon as I get the site restored to where it was last night.
Everything will turn out well, I'm sure. Any guesses as to how I managed to hit the dreaded red button? (no, no, not the RED button! 
)
Thanks!
~Kim