Second Amendment's gait was functional and that is about it. It was clunky, mechanical looking and inefficient.
SA's gait was very simplistic. Basically alternating diagonal sets of legs would be raised and moved. While this works it is sloppy and prone to wondering (unable to walk in straight lines). Also, due to program structure, SA was unable to both walk and turn at the same time. These things had to be improved!
Enter the ripple gait. SA is now programed with an eight step ripple gait (leg up and forward, leg down, move body forward 6x). In addition it is now possible for him to turn while walking opening a great amount of possible body translations.