Board Thread:Spoilers!/@comment-23906605-20131017110136/@comment-22525977-20131029030227

If he had chosen to stay with Emma, he'd have had ten years to slowly bring her around to the idea that magic exists and hey there's this curse up in Maine that you could break, we could do that.

Or, since he has so much faith in destiny, he could have told August to lay off, stayed with Emma, and left it to fate that she'd end up in Storybrooke at the proper time.

Or since he hates and is terrified of magic, he might've stuck around with the intent of being around when she went to break the curse to watch her back, or else tried to keep her the hell away from Maine.

Or just, anything that made Emma an active participant in what happened to her instead of deciding that he and August know best so let's just not tell her any of this, even though actually having a decade to prepare to dismantle this horrible curse wouldn't actually be a bad idea.