The Final Battle: Part 1 - S6-E22
Other mistake: While Killian and David are talking at the base of the beanstalk, in the wideshots we can see the protective black boot worn by Colin O'Donoghue, the actor playing Killian, who broke his left foot during filming of the previous musical episode. (00:20:30)
Tougher Than the Rest - S6-E12
Visible crew/equipment: When Sir Henry searches for his mother and The Evil Queen along the water's edge, in the shot where he says, "They crossed the river", as he turns his horse around, a horse wrangler's hand can be seen holding the horse's bridle in the lower half of the screen, guiding the horse to turn around. (00:04:20)
Revealing mistake: When Hook is running from the Lost Boys, as he clambers down a hill, you can see the face of Colin O'Donoghue's stunt double. (00:00:50)
Continuity mistake: When Mary Margaret drops by Emma's house to discuss wedding plans, in the wide shot where Emma's phone rings, Emma's flower tattoo (which can be seen in several other shots throughout the scene) is missing from her wrist. (00:04:15)
Continuity mistake: When Emma lands and Hook land in the apartment after going through the portal, Henry and Regina help them both to their feet. In the first shot, Regina is seen holding onto Hook's arm as he and Emma get up. In the next shot, she is holding onto Emma's arm. (00:34:45)
Continuity mistake: When Henry is sitting at the bar at the end of the episode, reading his storybook, in some shots, there is a picture on one page, which takes up the entire page. In other shots, there is a different picture there, which takes up only half the page and has text next to it. (00:37:25)
Continuity mistake: When Gideon shows his father the book that Belle gave him, "Her Handsome Hero", in the close-up, the cover of the book is facing upward. In the next shot, where Mr. Gold takes the book, the cover is facing downward.
Chosen answer: Even if one can see the future, it can be somewhat vague and left open to interpretation.
raywest ★
He can sees the future all jumbled up. It is like a puzzle, it is hard to put together, but even when he does put it together it is not set in stone the future can change.