Wow... fascinating post, and really nice info & links. ^^
Side-ramble alert! -- I'd never heard the word "Mittwoch" before, which I figure means "middle-week" literally. English is so funny to me because it's about half olde West German and about half olde Norman French, and I'm constantly seeing connecting words.
But not in this case! As English "Wednesday" is like Woden's (king of the Norse) day, which perhaps came out of Anglo-Saxon, and didn't make it in to modern German.
Okay, pardon all that ramble. :P