In college, my music history teacher always told us that "every instrumentalist harbors a secret desire to be a singer". (It was always startling when he said this-- he was the school's orchestra conductor and a semi-famous Cellist, and was often dismissive of singers as "lazy musicians").

More than any other composer (at least for piano), Chopin seems most gifted in his ability to write music that, for all intents and purposes, is singing with the piano.