Although Mary Poppins Returns is filled with songs, the writers cut many potential pieces from the final version. Songwriters Marc Shaiman and Scott Wittman are well practiced at the art of making musicals, having written the score for “Hairspray” and “Charlie and the Chocolate Factory.” Writing musicals always seems to require letting go. This article in the NY Post notes that of the 25 songs written only nine full songs remain in the film. NY Post – Mary Poppins Songs…