Discussing with folks recently about 'Flow Training'.
Many people have stuff they call flow training in their system, and I guess the general understanding of it is - any partner practice drill that moves smoothly between the players.
When I talk about flow training, however, I am thinking of something different, and it is all to do with the implication that the word 'Random' adds to the game.
Random implies that I do not know what is going to happen next, in fact neither party should be sure of what is going to happen next, even if a certain reaction is expected.
That is what makes it valuable, and not the same thing as merely moving in concert with another human being.
And this is also where the subtlety lies .... you are moving with them, because everything you do should be because of who is in front of you, how they move and what you are working on. It can be about accuracy, timing, range, openings, blade manipulation, whatever you like, but the part that makes it important, is that you are there to notice what people will do next ..... not know what people will do next.
Random flow does not need to be totally random like free sparring, or even broadly random, it can be limited with the addition of whatever parameters you choose, but even if the ONLY randomness is not knowing if the next strike will come left or right, if your opponent will react to your fake, or when the cut will come .... it is enough to change the experience, and what you learn from it.
It's uncertainty which is key, this is where the learning is. You can only learn how to 'see' if you learn to watch ... and there's no need to pay attention if it's everything is already known.