It’s a question that comes up time and again.
“Where’s the link between Kata and Kumite?”
“Why do we need to do Kata? It’s just boring and doesn’t mean anything”
“It’s just performance art”
The reality is it depends entirely on what your goals in learning karate are and where you are training.
We could go into the nature and history of kata and try and build an argument for why they are the core of Karate but there is only any point in doing that IF you train your Karate with Kata as the core and the fundamental centre of your training and if your Kihon and Kumite are there just to enable the practice of Kata based karate.
We could make an argument for the “tradition” of kata as a part of the art of Karate which is both true and not at the same time. It has become true as kata have been collected into the system and are practiced as one of the signature identifiers of Karate as an art. This gives us the classic 3 corners of Kihon, Kata and Kumite as a triangle, not a very coherent triangle admittedly but one that works if you accept it at face value and are happy to only ever try and link 2 of the corners at any given time.
So if you are practicing “tradition” you need them as part of the tradition otherwise what art are you practicing?
If you are practicing karate as a sport then it comes down to if you are doing competitive kumite or kata? If you are doing kata then they are obviously quite important, if you are doing sport kumite then they are next to useless. Don’t look for the link between sport kumite and kata because there just isn’t one.
If you are learning with a self-protection mind set then it becomes (or can appear to) a very grey area indeed.
It may be heresy to say it but there is nothing that you learn from the Kata that you cannot learn equally as well without them. They are a condensation of principles and technique into a compact and portable form that acts as a catalogue and reminder and gives you a way of practicing your body dynamics when a partner isn’t available (and a valuable set of drills when one is) but they are not magic.
There is nothing they contain which cannot be worked without referring back to the kata. I could teach a full set of drills and techniques (that come from kata) without ever teaching you the kata itself. You would walk away with some effective skills with no idea of where they came from or how they hang together in the form and they would be no less effective because of that.
Having said that, anybody who practices an art that has consistent drills to learn form, technique or body mechanics either solo or with a partner is effectively doing kata (whether it is two moves or twenty), they may just not be linked back to a “traditional” form but they are kata none the less. I have trained with many people who have a sudden light bulb moment and say “Oh, I recognise that move, it’s the same as we do in xxxxx”, and why wouldn’t you, there is a lot of commonality in most effective fighting systems (and it makes sense that there is).
So you don’t need kata to be effective but what you will do is spend a lot of time reinventing a wheel (or set of wheels) that already exist in order to have a coherent frame to hang your training off of.
So, you can have an effective art and skill set without kata but without kata is it Karate?
In answer to that I would tend to paraphrase Terry Pratchett here (Hog Father) with his discussion on whether the sun would come up or whether the world would just be illuminated by a big ball of burning gas.
Without kata you are not doing Karate, you are just defending yourself with empty hands.