Actually, as an old Lowrey organ player, like many a keyboard player, I am familiar with the expression pedal. It controlled the volume of the Lowrey organ, and was also used to switch to a minor key by a sidewards move of your foot. You should have heard some of the "expressions" it brought out of me while switching to a minor chord and the volume was either muted or blasted. I hated that pedal! I know the foot switch does a different job, but it also does the job that my old expression pedal did...and more. And, nowadays, my expressions are much nicer.