The official “Definition of Taekwon-Do” also includes this statement:
“Most of the devastating maneuvers in Taekwon-Do are based specially on the initial impact of a blow plus the consequential additional force provided by the rebound of the opponent's moving part of the body. Similarly by using the attacker's force of momentum, the slightest push is all that is needed to upset his or her equilibrium and to topple him or her.”
The first part of this statement reflects the hard style philosophy of force against force. The second part, on the other hand, reflects a soft style philosophy of using the attacker’s force against him and is reminiscent of Aikido, Judo and other soft style martial arts.
However, when we think of this soft style aspect in Taekwon-Do, it’s possible to make the two following mistakes:
Mistake #1: Thinking that soft style means weak
Because the descriptive “soft” is used, it is often thought synonymous with “weak” techniques. This is not the true meaning of “soft.” Anyone that has been at the receiving end of a Judo technique (Judo translates into “Soft Way”) knows that a judo throw is anything but weak. The video below shows a master of a very traditional form of Tai Chi easily throwing a big MMA guy during a training session. This is Chen style Tai Chi, the oldest Tai Chi form. The practitioner is Master Chen Bing, head of the World Taijiquan Association.
Similarly a hit from a soft style strike can be quite devastating. In the video below Glen Levy shows (off) his hammer fist punch which he attributes to fa jin, the method of striking employed by Chinese soft styles like Tai Chi.
Fa jin is a combination of relaxation both before and after the technique and extreme acceleration achieved through kinetic chaining. These concepts of conscious relaxation and acceleration through kinetic chaining are fundamental to power generation in ITF Taekwon-Do.
Mistake #2: Thinking that now all techniques should be performed soft style
Since ITF Taekwon-Do has moved away from being an absolute hard style, the temptation may be to turn it into a complete soft style. While it is plausible that under the guidance of some masters Taekwon-Do may evolve in that direction in the future, this is not where ITF Taekwon-Do is at present.
Actually, there is an ITF Taekwon-Do off-shoot that has gone this route. Grandmaster Choi Kwan Jo, one of Gen. Choi’s demonstration team members from the seventies, broke away from the ITF after injuries and reformed Taekwon-Do into Choi Kwan Do. His reason was that he believed that the hard style Taekwon-Do of the time was the cause for his injuries. When Choi Kwan Jo did Taekwon-Do it was during a time in ITF Taekwon-Do’s development when it was still performed primarily as a hard style and still very similar to Shotokan Karate. The major application of soft style principles introduced by Gen. Choi Hong-Hi into ITF Taekwon-Do only started in the 1980s.
The video below shows a Choi Kwan Do practitioner in action. Notice the emphasis on circular motions. Choi Kwan Do is a much more thoroughly and consistently soft-style than ITF Taekwon-Do.
No, ITF Taekwon-Do has not abandoned all its hard style techniques and principles. Rather, it has a peculiar combination of both hard style and soft style techniques, which is a manifestation of its two main roots – Shotokan and Taekkyeon. Sometimes, the same movement can be performed either as a hard style technique, or as a soft style technique, depending on the desired effect. We have for instance the guarding block which is sometimes performed in a more linear fashion and other times in a more circular fashion. Take the low reverse knife hand guarding block as an example.
ITF Taekwon-Do has evolved to include both hard styles and soft style principles and techniques which are reflective of its two main roots, namely Shotokan Karate, which is a hard style, and Taekkyeon, which is a soft style martial art. I don’t think we can say that ITF Taekwon-Do has changed from a hard style martial art (as it certainly was from the 1950s to the 1970s) into a soft style martial art. Rather, it would seem that ITF Taekwon-Do is attempting to be a hard style and a soft style at the same time. (This “soft” aspect should not be misunderstood to mean weak.) While ITF Taekwon-Do always had typically soft style techniques (i.e. circular motion techniques) derived from Taekkyeon and elsewhere from its beginning; it didn't really fully employ soft style principles (i.e. fa jin style power generation) till the 1980s at which time conscious relaxation of the body, knee spring (and its associated sine wave motion), and kinetic chaining concepts became especially prevalent.