@Ipstenu -

Plugins can (and do) write to wp-config.php all the time. See WP Super Cache for the most common one I know of.

Huh; learn something new every day!

Well, let me re-phrase: there's no way I'm letting anything write to my wp-config.php! Heck, I don't even keep it in the document root. (I'll keep an account named "admin"; but nobody's touching wp-config.php.) :)