I think of melodic content. I have no formulas worked out—I just play from the knowledge I have. Like, when you play a Gb chord over a C chord, it’s two triads— a Gb triad on top of a C triad. That’s where we get the two tonics, and if you voice it right, it’ll sound very pretty. But I never think about that when I play. It’s all done intuitively. All I think about is trying to create a melody. I try not to think about what scale I’m going to play for a G7 chord.