When discussing martial theory it is useful to establish certain guidelines: these would certainly include the dual natures of practicality and realism, as well as a generally universal approach which is to say an openness to effective technique or strategy regardless of its historical period and free from cultural prejudice.
This precursor gives us an immediate frame of reference with which to begin our examination of this infinitely complex matter. As a means of diving headfirst into this quagmire of contradictory suppositions and conclusions regarding the nature of combat, let us use two nearly diametrically opposed martial systems:
Brazilian Jiu-jitsu vs. Taekwondo
Many a would-be MMA-ist would balk at this seeming mismatch, but let us first state exactly what is the main theoretical premise in respect to these individual styles:
Brazilian or "Gracie" Jiu-jitsu operates from the theoretical standpoint that 90% or so of all street fights end up on the ground, therefore technique should begin with creating a situation where one can establish pre-designated positions of control on the ground with the subdued opponent, and conclude with the humane application of a technique of submission. This is indeed the irony of Jiu-jitsu and Judo technique, namely that the Japanese "Ju", equivalent to the older spelling still used by the Brazilian contingent "Jiu", which translates as "gentle" in the English language, indicates a technique of submission.
What is this "submission" technique? Quite simply a lock or hold which renders either incredible pain, a disabling of a limb, or an actual interference of oxygen to the brain via a choking-type maneuver. While these sound a bit brutal, they are actually the more humane of combative-type techniques. You see, these sorts of techniques can be applied gradually, giving the recipient an opportunity to give up or "submit", hence the term "submission" technique.
That these maneuvers result in either a broken limb, unconsciousness, or even death if applied to their extreme is an afterthought in comparison to the brutality that is boxing or kicking someone into unconsciousness thru punches or kicks to the face and head.
Now let us examine the main theoretical concepts of Taekwondo; I refrain to say Korean Taekwondo because just as Brazilian Jiu-jitsu is distinct yet one with Japanese Ju-Jitsu, the same applies to Taekwondo. You may easily attribute the following statement to nationalism on my behalf, but I now publicly declare that a team of American Taekwondo masters would easily defeat a team of Korean masters in bouts of MMA, NHB, Vale-Tudo, or even contests to the death.
This flag-waving aside, Taekwondo is an art which emphasizes kicking techniques as any person with even a rudimentary knowledge of martial expression knows. Not everyone however knows what lies beyond the flashy kicks of Taekwondo in respect to theory and technique.
To examine the Korean expression Taekwondo, we first break it into three distinct words:
Tae – To smash or destroy with the foot; the foot; the legs; foundation.
Kwon – To smash or destroy with the fist; the fist; power.
Do – Art or way; Tao.
So then Taekwondo means the art of feet and fists, or kicks and punches. This is an interesting almost prioritization in terms of favored fighting techniques. Let us ponder the pros of using kicks to defend oneself rather than other sorts of techniques; the legs are longer than the arms, thus you can keep a distance from your punching or grappling opponent using kicks and thereby neutralize their techniques.
Can a Taekwodoist successfully ward off the takedown attempts of a wrestler or avoid the punches of a boxer? Well this then becomes a matter of individual skill, physical attributes, and the ever-present element of chance that is a factor in all fighting encounters.
Why are kicking techniques preferable to other sorts of attacks beyond distance or let us say as a result of distance? Punching techniques often end up near the mouth or teeth of an opponent in a live or realistic situation (a street fight). There is a very real danger of infection involved in this particular instance. A kicking technique is usually delivered under the protection of footwear. That a person can operate from this perspective daily in today's urban landscape and wear heavier or combat-considered shoes or boots, obviously amounts to dealing out blows with near or actual weapons.
Secondly, as the name implies, Taekwondo's second line of defense is the fist, or boxing technique. In Taekwondo's infancy in this country, it was in the same state as American Karate, and that is to say that the punching techniques accompanying the kicking and footwork were of the traditional, or "reverse-punch" method, or of the variety which features the non-punching hand fixed to the fighter's side. The traditional method of dealing punches is inferior to the contemporary western boxing method, just as traditional Ju-jitsu is inferior to Brazilian or contemporary Jiu-jitsu.
These bold statements need not seem so, for Bruce Lee himself was of the publicly voiced opinion that western boxing was the most effective method of using one's hands. No one can debate the fact that the Brazilian/Gracie method of Jiu-jitsu has come to dominate not only the Ju-jitsu world specifically, but has also revolutionized the entire culture of combative arts on this planet.
So then it was the responsibility of early American Karateka to modify their punching techniques to incorporate this more effective variation, which many did, giving way to the sport of American-style Kickboxing. There were a number of their Taekwondo counterparts who did likewise, however the main body of Korean Taekwondoist went the way of the W.T.F. and the newly emerging "Olympic-style", which removed punches to face and head altogether, thereby avoiding the issue.
The Olympic-style is a rule set which creates the possibility for some very extreme violence with the foot to the head and torso, just as a Jiu-jitsu match disallows ALL strikes in order to create the probability of a submission outcome. This being said, for a realistic fighting situation where face and head punching is the main attraction so to speak, it is safe to say that a Taekwondoist versed in western boxing along with his Taekwondo technique would be comfortable in the presence of boxing.
On to the realms of wrestling, Jiu-jitsu, Thai-boxing, Aikido, Kali or any other method whatsoever, Taekwondo is an art which is subject to evolution as it has its roots in the military culture of Korea, which is intrinsically progressive, as are all effective military bodies. So then, the Taekwondoist is free to incorporate other methods into his style in order to address any situation or skill set whatsoever.
Typically speaking however, Taekwondoists utilize Hapkido techniques in their close-quarter situations.
Another major factor to consider when comparing Taekwondo and Jiu-jitsu theory is the matter of practicality, namely the reality of a person having to deal with multiple-attackers. Jiu-jitsu technique can only be applied to a single attacker. This is a facet the basic striker vs. grappler debate. Humorously, in the Renzo Gracie book "Mastering Jujitsu", author John Danaher avoids the issue of Jiu-jitsu's impracticality in a multiple-attacker scenario by basically stating that no one can effectively defend themselves against multiple oppnenets. Considering this fellow is a doctor, it wouldn't surprise me that he hasn't been involved in many gang attacks. But as a survivor of many such public encounters, I tell you he is mistaken.
These comparisons should have hopefully illuminated the nature of martial theory in general, and the contrast between these two arts in specific. The realms of martial theory are both wondrous and convoluted. Martial theory is not science even though it utilizes a scientific approach to fighting. With more in-depth understanding of particular theories and methods, a practitioner is better able to formulate their own fighting hypothesis and method. This would seem to be the product of Bruce Lee's work, and indeed maybe it is…