Revealing mistake: In the soda shop, the waitress turns off the lights with her elbow because her hands are full, but she misses the light switch by 6 inches. (00:55:10)
Revealing mistake: During the "Red" number in the Emerald City, a large screen is supposedly telecasting from the walking camera focused on the dancers below. Watch closely and you'll see the dancers' movements do not coincide with the movements displayed on the screen.