There is some disagreement in the karate community about whether hidden techniques in kata actually exist or not, but that disagreement largely stems from differing views on what the definition of “hidden” is. In the sense of karate techniques, “hidden” could be used to refer to things that are purposely concealed or obscured, or even completely removed. It could also be used to refer to things that are simply not obvious to the observer, or things that are implied, but not explicitly shown by the kata. Generally, these techniques are called kakushi-te (hidden hand), or kakushi-waza (hidden techniques). It is often suggested that kakushi-waza are secret techniques that had to be hidden because they are “too deadly” to show publicly, but I tend to regard such claims with suspicion, as they are often used as a marketing ploy, or to hide a lack of knowledge. When it comes down to it, kakushi-waza are usually only hidden from those who do not know what to look for, or do not understand what they are seeing.
Many kakushi-waza simply occur naturally within a larger movement, making them difficult to see. Sometimes, these are emphasized in different versions of kata, so it can be useful to compare how the same kata is done across various karate styles. This tends to happen when something appears to be one movement in the kata, but actually does more than one thing in the course of that movement. Probably the most common example of this is mawashi-uke (turning receiver), which can be seen in the animated GIF, above. At first glance, it looks to be a single movement of the hands turning and pulling back, and the fact that it has one name seems to support that. However, if you look closely, you will see that there is much more going on. In the above example, you see that the right hand extends while the left pulls beneath the right armpit, then the right hand turns over and pulls back, while the left hand climbs the right arm, then the right hand pulls all the way back and turns over, while the left hand rises, hooks, and turns over as it pulls down. When broken down in this way, it is quite easy to see that this is not one movement, but many.
For a more basic example of kakushi-waza within larger movements, we can consider shuto-uke (sword hand receiver). This is another technique which appears to be one technique, but is actually doing several things at once. In the animated GIF, above, you can see how the “setup” position of shuto-uke is used to both deflect an attack and strike at the opponent’s eyes, and then that hand withdraws to control the attacking limb while the other hand chops to the neck. Parker Sensei then shows how a second shuto-uke movement (they often appear in pairs and triplets in kata) can be used to move the attacking limb across the body to be trapped and locked. All of this can be done with just “one technique” (shuto-uke) because of the smaller movements hidden within it.
In some cases, kakushi-waza are movements that are explicitly shown in the kata, but have shrunk, or otherwise become more subtle over time. Often, this is the result of aging instructors modifying their kata to fit their bodies, and students copying their teachers. Sometimes, it is a stylistic choice, based either on aesthetics or a decision to remove emphasis from a certain application that an instructor doesn’t like, without completely removing it. An example that can be easily compared is the uraken-uchi (backfist strike) motion, which is sometimes done as an age-ura-tsuki (rising back thrust, or uppercut) in Naihanchi Shodan. The strike, itself, is generally preceded by a receiving motion, sometimes called haiwan-nagashi-uke (top-of-the-forearm flowing receiver). In the animated GIF, above, you can see how this movement has been emphasized, and made to be very large. Compare that with this version, done by a student of Maeshiro Morinobu Sensei, which is a smaller movement that only circles on one side of the head. For an even starker contrast, we can compare it with Chibana Chosin Sensei’s approach, which circles the hand in front of the face, using a very small motion. All of these are different representations of the same movement, and because they are emphasized differently, one can see different applications for them. When a movement becomes as small as Chibana Sensei’s example, it can actually be difficult to see what it is meant to be without comparing it to other versions, effectively making it “hidden,” or more accurately, “obscured.” Coincidentally, this movement also contains multiple movements, just as our previous examples do, and comparing these different versions can make those multiple movements more apparent.
I sometimes like to say that parts of kata were “written in shorthand.” That is to say that some techniques are implied, and given placeholders in the kata, without actually being explicitly performed. One example of this is when the kata have you perform the entry to a throw, without actually acting out the throw, itself. I mentioned this idea in a previous article on kosa-dachi applications. The most common example, however, is the humble neko-ashi-dachi (cat foot stance). This stance, in some form or another, appears in just about every karate system. While it does many things, its primary function is to lower your center of gravity and pull it back over your rear leg. This leaves your lead leg free to kick, knee-strike, or sweep an opponent, depending on the range you are at and what your opponent is doing. In fact, if you watch someone throw a lead-leg kick, or a knee, or even some sweeps, from a fighting stance, they will naturally transition through a position very similar to neko-ashi-dachi. For this reason, the stance can generally be considered to be a placeholder for some type of lead-leg attack.
There are some instances where techniques are intentionally altered, or omitted from kata, entirely. This type of kakushi-waza is the most difficult to point out specific examples of, because unless you practice the style that has changed the kata, you won’t know what has been changed. On top of that, revealing the change would defeat the purpose of changing it! This is often done to create separate “private” and “public” versions of a kata, which makes it simple to determine who has legitimately trained in a system, and who has not. For example, one might change something small, like a hand formation from an open hand to a fist, or take out a repeated sequence, when putting together a book on a kata. Similarly, for demonstration and tournament purposes, one might change small movements to larger ones, such as changing a step to a jump. This serves to not only make the kata more aesthetically interesting (in the case of demonstrations and tournaments), but also to introduce “flaws,” so that someone watching or reading the book could not simply copy the kata and claim to have trained in the system. Essentially, it is a low-tech way of keeping people honest.
All of these examples, with the exception of techniques that have truly been intentionally altered, are only “hidden” to those who do not know what to look for, or do not understand what they are seeing. This can be made worse by speed, even when someone shows you how to apply the movements. My Sensei’s video, above, is a good example of this. If you were to only see the technique once, at full speed, it would be very difficult to pick up on all of the little strikes that occur within the larger movements of the technique. With this type of subtlety, it is easy to see how these kakushi-waza could be easily missed, and lost to the sands of time. For that reason, it is important that we do our best to research different variations of kata, and analyze the subtle details when working on applications for those movements.