12 notes in an octave, each major and minor... so 24 right? Not so, according to Vic: His argument is: for the major scale, you can have either: zero sharps/flats, 1 - 7 sharps, or 1- 7 flats. 15 total. Count the relative minors and you get 30. It's obvious he's double-counting enharmonic keys. Why? Is there a benefit to thinking of, for example, Db major (5 flats) as C# major (7 sharps)?