Amusingly, Gesualdo and Zarlino are amongst the ten contemporaries of Palestrina(well, if you are a nerd, it's funny)--the Gesualdo remark is funny because Gesualdo had inherited wealth and political connections, so he didn't need a patron or an audience and could do whatever he wanted. He reputation for getting away with murder, figuratively, by using chromaticism and dissonance, and literally, by killing his wife and the Duke of somewhere or other when he caught them in flagrante delicto-

The Grandmother Chord was invented by Nicholas Slonimsky(who you may recall, used to play the piano with an orange on the Tonight Show from time to time) as kind of a musical joke(he also wrote and played musical palindromes, and may have even invented them) they included all twelve notes--which is why you'd want twelve fingers--

Funny also is the business about augmented sixth chords, which come as either German, French, or Italian, and are actually enharmonically, additional kinds of seventh chords--

Well, I think it's funny, though, if you aren't interested in counterpoint you might not give a Fux--