Using the lesson I learned from that Mozart performance I prepared to perform a Haydn sonata yesterday by not practicing it at all. I practiced around it, so to speak--a trick I learned many years ago while preparing to perform Schubert's Lovely Milleress song cycle.
I realized that practicing the actual accompaniments would guarantee their lifeless performance. (This is a form of ritual murder to which we become inured when hanging out with the wrong crowd.) Thus, with an open ear and attitude of curiosity I discovered yesterday a fascinating tonal relationship in the sonata which had never previously been apparent to me. I had so much fun tracking this new found delight that it was like playing the piece for the first time.
One of the audience members commented that it was not like the usual Haydn. I think the "usual" Haydn is a creation of teachers who have tried for years to make a Classical composer out of this most inventive man whose insights bridged two distinct eras. His piano sonatas evoke Baroque vocal sensibilities from the newfangled piano. Whenever I play these astonishing pieces I can feel Haydn's socks being knocked off by this amazing instrument.