Jennifer Dunning for The New York Times

A great deal has been said and written about "The Hard Nut," Mark Morris's production of "The Nutcracker," which opened on Tuesday night and will be performed through next Thursday at the Brooklyn Academy of Music. But no one has summed the piece up better than Mia Sanchez, a young dancegoer who is quoted on posters for "The Hard Nut." "It was weird," the 9-year-old critic wrote, "but I loved it."