To understand the 常行 (Joko) series of kata, designed by Asai Tetsuhiko Sensei, one needs to understand their theoretical basis (pros and potential, not only potential but real, cons); furthermore, the achievement objectives that they collectively set out to attain.
There is an interesting story behind Joko that nearly answers all of these questions—which I believe you will find is fascinating, if not genius—and I’ll will outline this today.
Before doing so, for those who are less familiar with Asai Sensei’s karate, I want to stress that “…the Joko series are not 古典型 (Koten-gata/Ancient/Classical kata, nor formulated/reverse engineered directly from them) as often claimed”; rather, they are kihon training kata created by Asai Sensei. Moreover, Sensei made them primarily ‘theme based’ for optimizing the training of the foundational techniques; thus, while there are applications, they are not so direct (but, rather, underpin actions). Taken as a whole, “…the five Joko are ‘higher-level’ 順路 (Junro)”.
Ok, so now that is out of the way, allow me tell you a fascinating story.
Asai Sensei was an avid reader, and if you ever visited him at his company office—Futami Tsusho—in Shinbashi, he’d often visit the local bookshop. He had a wide range of interests, one of which was classical music which, again, he greatly enjoyed reading about.
That brings me to the Joko Kata. As you will probably know the name Joko basically means ‘always do’ and the labels ‘Issei’ to ‘Gosei’ translates as (first to fifth) ‘energy’/‘force’/‘authority’/‘vigor’/‘influence’/or ‘impetus’. As I’ve stated in the past this kanji for 勢 (Sei)—for most Japanese—immediately brings the power of physics to mind. In Asai Sensei’s terms ‘natural energy’.
All right, but that obviously still doesn’t provide the complete story…. Allow me to link classic music, with these kata, via Charles-Louis Hanon (1819 – 1900); in particular, his most famous publication: ‘Le Pianiste virtuose’ (The Virtuoso Pianist).
This classic piano textbook—first published in Boulogne, in 1873–is “…a compilation of sixty exercises meant to train the pianist in speed, precision, agility, and strength of all of the fingers and flexibility in the wrists.”
“The exercises are intended to address common problems which could hamper the performance abilities of a student. These include "crossing of the thumb", strengthening of the fourth and fifth fingers, and quadruple- and triple-trills. The exercises are meant to be individually mastered and then played consecutively in the sections they are placed in. Apart from increasing technical abilities of the student, when played in groups at higher speeds, the exercises will also help to increase endurance.”
Here’s a quick summary of ‘Le Pianiste virtuose’… You’ll notice, consistent with the aforementioned aims, it sounds like a karate textbook!!!
Part One: Exercises 1 – 20 are "preparatory exercises",
Part Two: Exercises 21 – 43 are referred to as ‘further exercises for the development of a virtuoso technique’.
Part Three: Exercises 44 – 60 are high-level ‘virtuoso exercises for mastering the greatest technical difficulties’.
Yes, this is all ‘kihon’ for pianists, nonetheless, it is ‘hard core kihon’. It is this work of Hanon—in its entirety—that ‘inspired the Joko series of kata’ and sums up their purpose.
Does that mean the Joko kata are good for everyone? The answer is clearly ‘No way!!!’. Interestingly, the same goes for Hanon’s 60 exercises. Many contemporary piano teachers claim that they are not good for technique as they take up too much time. Furthermore, they insist—for the person not seeking an ‘extreme level of technical skill’—believe it is better to go straight to Mozart, Beethoven, Chopin et al.
This is the basis of Hanon’s exercises—extreme skill in the ‘basics’—and, indeed, the five Joko kata. Who would imagine that Hanon is an influencer of Asai Sensei’s creativity and teachings? But he was! There are other such situations as well, however, I’ll stick to Joko today.
Needless to say, this type of practice is not for the faint hearted. It is ‘deliberate practice’ requiring deep mental concentration and physical effort whilst simultaneously offering very little joy. To explain this, the investment of training is very high and ‘the returns’/‘gains’ are slow to come; that being said, if somebody wishes to get to a really exceptional high level and is really tough, the investment is worth it.
To conclude, I really hope that this article was worthy of your read. If you are interested in more information about Joko, here is another article which will further your understanding: http://andrebertel.blogspot.com/2018/10/joko-issei-gosei.html