Few things are as critical yet as glossed over as footwork. With proper footwork the body can be moved in an efficient way while maintaining balance, creating driving power for strikes, providing hip availability for throws, and more.
Kata attempts to teach us about footwork, but it's easy to get caught up with what the hands are doing and simply bring the feet along for the ride. In fact, the effectiveness of bunkai can be made or broken depending on how the body orients to the opponent. Discovering some of the more effective applications in kata requires careful attention to body movement.
Ultimately there are only a few ways for the body to get from A to B, but an infinite amount of subtle ways to improve that process. One important concept in karate is known as "diamond stepping", which allows for removal of target, aggression, defense, momentum swing, and balance. In total it allows a practitioner to use virtually all the tools available to a karateka during a combative engagement. Interestingly, this very same concept shows up in other styles as well, going as far back as the Bubishi itself.
Diamond Stepping in Action
The following video shows how you can integrate the diamond step concept into your training. It will also demonstrate a series of techniques from different styles, including Okinawa Kenpo, Aikijujutsu, Motobu Udundi, Kobudo, and more. The goal is to demonstrate how a fundamentally sound concept can be pervasive throughout many different styles. As a bonus, at the end of the video I practice some freestyle randori type of techniques, allowing students to attack me in an unscripted way and seeing what kind of defenses come out of it.