Quote Originally Posted by Buffalobiian
He had difference plans for different scenarios, including one if they didn't fall for the Chakra Blade Shadow Bind. He just didn't expect them to break out of it once they're caught, so it took Shikamaru by surprise.
Actually, given that its Shikamaru we are talking about, I fully believe that he had a plan for "what if they can break the Shadow Bind". I do think he was suprised, but I think its either because they didn't do it immediately or because of how they did it, not just the fact that they did it.