Chris Pepper, Master Editor, pointed out something I missed. If you memorize an encrypted network, your iPhone won’t connect to an unencrypted one with the same name, or one with a different password. Thus unless the bad guy knows your WPA passphrase (you’re not dumb enough to use WEP, are you?), you can memorize your home network and not worry about accidentally connecting while wandering around, even if it’s still called “tsunami”.