Timing and spacing in kata

Kata practice is usually thought of as restricted because you know what's going to happen. In good practice, you do know the movement of the kata. What you don't know is the timing, the distance, the speed, or the power your partner will be using. Traditionally, kata practice is done with a beginner doing the winning role, and a senior practitioner taking the losing role. It's the senior's job to control the timing, speed, distances and power.
It's one thing to know what the next attack is going to be. It's another to act at the right moment, move the appropriate distance, and do it fast enough and with without moving too much or too little. The first kata in the Kendo No Kata is simple, but teaches all of these lessons. The kata is nothing more than opponents approach each other, one attacks, the other avoids the attack, then counter attacks. That's all that's required to learn though. There are several critical lessons in this kata.

The first lesson is distance. What is the distance of engagement? This is fundamental. At what point is someone close enough to be a true threat? If he's too far away to be a true threat, you don't need to act. It's a threat without teeth. How close is too close? It's different for every person, based on reach, step length, what weapon they're using and other factors. Without this one, you'll never get to the technique.

The important parts of a kata

There are lots of kata around, from the kata of karate and iaido, to the very formal and seemingly fossilized two-man kata of koryu kenjutsu and jujutsu to the fairly loose kata of standard aikido practice (and yeah, most aikido practice is definitely kata). But what are the most important elements of kata.

It the techniques that everyone sees and focuses one. In karate, the kata are mainly about how to strike and block. In iai they are all about learning to draw quickly and with control. In koryu arts they are about learning the techniques for destoying your opponent. Or are they?

To me, the essence of kata are in how they deal with spacing, timing and the rhythm of the attack. The techniques are pretty much incidental to the primary lessons of the kata.