Having learned said lesson prevents me from using the title that originally occurred to me: The Stupidity of Brilliant People.
So once again I've been hinting about this idea in the back of my mind, and I'm investigating several portal, bulletin board and blogging packages to see what capabilities are available. As much as I love Movable Type I'm not pretending it's the Universal Hammer. At the moment I'm looking into PHP-Nuke, Wordpress and YaBB SE. Meanwhile, I'm plotting improvements to MTClient and generally keeping my plate full.
Now, I have some friend that run a bulletin board on Boardnation, which runs a customized version of YaBB SE. I told them about the now-expired free hosting offer from 1and1.com. Having taken advantage of it myself to set up a discussion board and development blog for MTClient, I offered to set up their board for them. We chose YaBB SE for its familiarity. All was smooth and cool, went wonderfully well. Until I tried moving the site from a subdirectory to the root directory of the account.
I decided to back up the database tables, reinstall YaBB SE, and restore the data to the new tables. What I did NOT decide to do, but did anyway, was connect to my own 1and1.com account when I looked up the database info for the second install. I wound up with the PHP code on one site accessing the database of another (mine!). But here's the REALLY stooopit part…when I inserted the data from the original install, I noticed some tables whose names started with mt_ and I'm like, "Huh? How'd they get there?" And I deleted them. Yup. I dropped the tables that support my development blog.
Of course, this causes all manner of stupidity. Fortunately, my friend's database was intact so I was able to get everything back to where we started the day but one directory level higher. And I guess I'm spending the next few days getting my development blog back on its feet.