Revealing mistake: When Bond throws a Blofeld henchman off a cliff near Piz Gloria in the Alps, you can see that it is a dummy, as its arm swings round and wraps around the whole dummy.
Revealing mistake: In the opening sequence when Sundance shoots the gun belt off the card player, the film was cut to make the quick draw appear faster. You can see Butch's image jump across the screen in the background.
Revealing mistake: Sam is supposedly far away from civilization, but throughout the movie you can see a ski slope in the background. (00:16:05)
Revealing mistake: When Wyatt, Billy, and the stranger they had just picked up are sitting at the campfire their shadows on the rock are not in any proper projection from the fire, plus, they are totally still. (00:22:10)