Let’s get this straight. Classical martial arts kata are not practice fighting. They are not what fighting is or was. Martial arts kata do not simulate combat conditions. They do not recreate actual combat scenarios. If kata aren’t any of these things, then what are they, and why bother with them?
Kata are pre-arranged training sequences. Kata are training scenarios for learning about essential elements of conflict. I train in both classical and modern Japanese martial arts, and both use a lot of kata. Classical arts tend to focus almost entirely on kata training. Gendai arts like Judo use a combination of formal kata training, randori/sparring, and informal kata.
Kata are not for mimicking combat . Kata are for getting better at combat. They are a training tool for learning the skills necessary for dealing with combat. They are an exceptional tool that has survived hundreds of years of testing and application. As a training tool, they provide a framework for practicing various aspects of combat, not just repeating techniques or practicing in a sparring situation where much of what is effective is not acceptable because of the risk of injury.
Kata is not sparring, and with good reason. All sparring assumes a dueling scenario. 2 people faced off and fighting. Any equipment is equal. There are no surprises, no unexpected changes. There is an assumption of fairness. Kata is not handicapped by any of these of these assumptions. Kata allows a much broader investigation of conflict conditions.
Classical martial arts kata generally start out simple, but they rarely assume anything is fair or equal. Araki Ryu Kogusoku is famous for one of the first kata taught to its students. It assumes asymmetrical armament (tori has a tray, uke has a tanto), and applies surprise to defeat the better armed opponent. There is nothing fair about this situation. It is unfair and tricky and applies deception. Just like a lot of conflict in real life. Sparring is worthless for learning these lessons.
The kata of Kodokan Judo, unlike the games of Olympic Judo, rarely assume anything is fair or balanced. The Kime No Kata is a great example. It is a set of kata of encounters between two people. One person, always unarmed, is attacked in sequence in a variety of scenarios. First the two are kneeling facing each other, as if talking, and one, uke, attacks the other in a variety of unprovoked and basically surprise attacks. Then uke attacks from the rear. After that a succession of attacks with a knife from the front and side. Then both stand up and there are unarmed attacks from the front, side and rear, followed by attacks with knife, stick and sword.
Sparring is extremely limited in so many ways that kata is not. In all of these jujutsu kata, the only thing the person being attacked, nage in Judo terminology, know is what attack is coming. They don’t know when, or how fast, or from what range, or how strong the attacks will be. Uke has complete control over these.
One complaint sparring enthusiasts often make about kata is that you always know what attacks are being made, so it’s never a surprise. The same is true in sparring. In sparring a very small set of techniques and attacks are allowed, and the vast majority of possible attacks are excluded under the rules. On top of that, in sparring the attacks are always coming from the front, eliminating 75% of the directions attacks come from. With it representing such a tiny fraction of possible encounters, sparring seems quite overrated as a training method for anything except sports encounters.
Another thing kata isn’t is completely prearranged. Kata leave a lot of room for changes in range, timing and rhythm. In koryu bugei systems, the uke is always supposed to be the senior, more experienced person. It’s uke’s job to control the speed of the kata so their partner is always learning and being pushed into new territory. In addition, just because know exactly which attack is coming doesn’t mean handling the attack is easy. No one tells uke when he has to attack. Uke gets to decide the exact moment of the attack, its speed and intensity. I have had uke’s drive me completely helpless just by drawing out the attack a little bit and then drawing me into responding at a different rhythm and speed than they attack with. This left me wide open with a big stick incoming at speed and completely unable to do anything about it.
Kata isn’t locked into one interpretation. Uke’s job is to adapt the kata’s speed, intensity and range to the student’s level so they learn as much as possible from the training. Kata also isn’t locked into just one uke. If you train with many different uke, each will bring different things to the training, things that make each practice of the kata unique. Different sizes, heights, strengths, speeds and levels of experience in each uke all combine to change the kata every time you do it.
Kata doesn't have to work every time you do it. In fact, when you are learning, it shouldn't work a lot of the time. You should be making mistakes and your partner should be stopping to show you why that particular way of doing it won't work. There is abundant room in kata training for failing. Are you getting bored? Then uke should ramp up the speed so you are having difficulty doing the kata. Or get a more powerful uke. Or one who is difficult for your to read. Boredom banished. If you are practicing kata in such a way that you can always make it work, you're doing it wrong.
Kata isn’t some dead, fossilized thing that you trot out to see how things were done at some time in the past. Kata are vital and alive and being changed and adapted all the time. No one says you and your partner can’t decide to try the kata differently and see what an appropriate response would be if you change one element. For advanced students, that’s a great thing to try. The creation of kata isn’t over either. People are creating new kata all the time. Most new kata don’t end up being preserved and passed on, but sometimes the kata have enough value that they are added to their system. The history of styles like Eishin Ryu and Shinto Muso Ryu show how things were added to these systems down through the centuries. Gendai budo do the same. Kodokan Judo didn’t create the Kodokan Goshin Jutsu until the 1950s. Over time, kata get tested, and the worthwhile ones are kept and passed on, while the others are dropped and forgotten.
Kata are a teaching method for practicing the most fundamental and important aspects of conflict. They are a time tested method that allows you to practice all sorts of dangerous attacks and defenses in a controlled manner. Kata allow attacks from every angle at all sorts of speeds and force levels, and they allow that practice in all sorts of asymmetrical match-ups. Kata give practitioners the opportunity to practice these match-ups at a variety of speeds, strengths and intensities, so they can grow and their skills progress.