I'm making a tool to help plan chord progressions, and I'm wondering what the starting options should be.
You'd think maybe diatonic chords would be the answer - Fly Me to the Moon, in C, starts on Am, Sweet Sue, in G, starts on Am. My Funny Valentine, the same. All My Lovin', in C, starts on Dm.
But no! Sweet Georgia Brown, in G, starts on E.
More than 9/10 songs do start on the key chord - particularly if we don't include anacruces, and of the rest, 9/10 will start on diatonic chords. Figures not too accurate, you understand!