Comment by Double_Cast

I memorize chord progressions in terms of interval-number. E.g. {F# m; B dom7; E Maj} becomes {ii; V7; I}. I've memorized which intervals are major chords and which intervals are minor chords. So if I can figure out the tonic, then I can figure out the key. And if I figure out the key, I need only remember a pattern of ordinals (modulo non-triads).