What ever method decided, I cannot expand any higher on my transposition training I received from Mick Dennisen when he was teaching me at the University of Cincinnati College Conservatory of Music. At the time he had me run through many, many months of mental torture (like learning a new language with EVERY key change), it has paid in spades many many years later. Whether playing off the piano score in small group ensembles or going though various versions of Organ Music in so many keys for non-Bb instruments, it has been a real career enhancer to go into to any new performance rehearsal and playing off a score with my Bb trumpet in hand, and play any original keyed arrangement with minimal effort.