Many martial arts use music as a basis for their application of movement and technique. Look at the traditional fights of Muay Thai or the fascinating Brazilian art of Capoera for some fine examples of this.
Music, or more specifically the rhythm and timing associated with it has strong connections with all martial arts, including karate. Whether you twang a string on a guitar, whack a snare drum, blow down the end of a trumpet, hit the keys on a piano or indeed strike the opponent - it's all based on the universal application of rhythm and timing.
All beautiful music is made up of 12 fundamental notes. However it is not the notes themselves that makes each song unique, but the strategic placement of gaps, transitions and varying emphasis. Notes without gaps is simply noise!
As soon as we begin to combine multiple techniques together, a rhythm is naturally created that incorporates not only the techniques themselves, but also the gaps in between them. Take a moment to close your eyes and listen. Can you hear any sounds? Great, now draw your attention to the gaps between the sounds. Both the sounds AND the gaps are required and are equally important to provide the unique stimulation that your ears experience at any one time.
The performance of karate kata is very similar to the listening exercise described above. You must take into account not only the techniques but also the gaps (i.e. transitions) between them. These are what help stitch the kata together and give it life. How the movements and transitions of the kata integrate essentially defines the rhythm of the form. Simply put - even if you keep each technique identical, if you vary the transitions even slightly then you ultimately change the rhythm and thus, the kata.
Many practitioners would advise completely against the alteration of kata, but I feel somewhat different to this in certain circumstances. I believe that the kata should become an individual expression and so long as the core principles upon which the kata rests remains intact, then it is in my view quite healthy to express the form in different ways during study, experimenting with timing, rhythm and emphasis. Done for the right reasons, this way of practising kata can be quite enlightening.
As an example of the above, let's take a simple jab/cross/hook punching combination. Now look at the variance of rhythm below by simply altering the transitions:
Jab - Cross - Hook
Jab ----- Cross ----- Hook
Jab ----- Cross - Hook
Jab - Cross ------ Hook
The individual techniques themselves do not alter, but the whole feel of the combination changes simply due to the variance in the transition between one technique and the next.
When someone in the dojo is performing kata, close your eyes and listen. You'll find that the character of each movement comes out through the inherent rhythm and the song that's played back to you is unique to the form itself. It becomes possible to be able to identify the kata without even having to look at a single technique. Try the exercise again, but this time alter the transitions. Change the pauses, speed up slow movements and slow down fast movements. You'll find that the kata becomes almost indistinguishable from the first.
Here's another exercise - Have a member of your dojo clap a rhythm of five beats and then immediately copy the exact rhythm using a selection of strikes against pads. Change the rhythm and then change the application. This encourages greater focus on the transitions between the movements.
So, what happens to the application of movement then when we alter the transitions? Indeed, how do we know that the kata we practice today always had the same rhythm and was never altered since it's conception? What if a slow movement is performed fast? What is a fast movement is performed slow? What if one movement and the following movement are put together as one? What happens when two simultaneous movements are pulled apart to make two separate ones?
In my view, the holistic study of kata should always involve a questioning attitude and experimentation, creating a journey that promotes consistent growth by progressively stretching our understanding. Do not allow tradition to bind you, but instead feel free to become malleable with what tradition has left us.
"Teachers open the door, but you must enter by yourself."
"Do not seek to follow in the footsteps of the masters; but instead seek what they sought."