I may not be a member of a particular wiki project but I have worked as a professional opera singer, been in professional musicals, and hold a BME. I'm not exactly a novice in the field. If it is a musical like you say than there should be some scholarly sources to back up that claim. Perhaps a biography of Hammerstein or a history of musical theatre would discuss the work in that context. At the moment your conclusion is clearly WP:OR based on the sources provided.