Don't hate me. :)
Okay, we're no longer getting the empty row. Yay!
But here's another wee little oddity (and this might just have to be the way things are)...
1. PHP myadmin - edit the slug and ID of a blog's term
2. Check the fix term box and click submit
A new record gets created in the site categories table, with the next incremented ID. The edited row in the blog's category table gets set to the new site categories ID. The name in both tables becomes the slug.
1. PHP myadmin - edit just the slug (or just the ID - both result in the same thing)
2. Check the fix term box and click submit
A new row is created in the site's category table with incremented ID, no term and the edited slug. The blog's row ID gets change to the new site category's id.