the large question is this: if you were to play against wgd and see orchard, misty, and no green spells, would you board for dragon combo or oath of druids?
Specifically on this topic, I've seen this before, and in my opinion it's one of the classic mistakes of sideboarding. Enchantment hate, or just bounce, is equally devastating to both Oath and Dragon. It would be devastating to sacrifice deck strength on a gambit, hoping to trick your opponent, actually succeed in tricking them, and then lose because they cards they boarded in to beat oath (maybe e truth, ray of revelation, diabolic edict) beat Dragon anyway.