In the very last scene, our vengeful hero could have easily walked to the Antonio Banderas character, but instead climbs the house before climbing down to a surprised face. Does that make sense, or is it mere script badness? Surely this was not done just for the sake of suspense?
I have spent some time looking through interviews with Antonio Banderas, movie reviews, and other information on Haywire. I have not found a single explanation for that scene, except that it might set up a sequel. I would have to say that climbing over the roof was purely for effect, in order to scare or surprise the recently revealed "mastermind" in the movie. With that over-the-top action, it gives the scene a "he won't make it out of this alive" feel, because he is so completely outmatched by her skills. So, it seems to be on purpose and totally for effect.