Martial Art Technique is meant to improve one's natural movements in combat, not to restrict it and not to replace it.

I think all of us who have gone to a dojo at some stage in their lives know about someone like this in class-
a boy or girl who has received belt after belt in gradings and whose basics and kata are exemplary, but whose kumite is really bad and who- to be frank- just can't fight... 

True- The disadvantage may in many cases be psychological, but another poison- which is especially fed to students who have never fought before in their lives, is that those blows, kicks, blocks (oh don't get me started on blocks...) and stances are effective for use in actual combat.

Truth, however, is that they aren't.

Why do we practice them this way then? I have actually given the answer to this question a couple of posts ago when I discussed the three elements in martial arts. Now those techniques are supposed to develop power when practiced regularly. As for technique itself, you really have to find that element in the technique that makes it work, preserve it and make it a part of you and discard the inessential bits that are not necessary. I really don't give a flying f*#k about whether my fist is level with my shoulder in the parry that I actually use to deflect my opponent's punch or that my shoulders are not square when I punch into his sternum.

What I do care about is that my blows have the necessary speed and power, that my footwork and body positioning is efficient and that I am not creating unnecessary openings.

The fact is- whatever style you learn is just part of what enables you to defend yourself. Your style may not encourage ducking, jumping, hooking or whatever else, but discarding those movements may cost you your life. Instead- you should incorporate such natural movements into your arsenal in order to make them work for you, rather than against you.

For example- I used to get angry at myself for turning away from my opponent in karate matches when I was under attack. And yes- because it was not part of my arsenal it only put me in more danger. Later on, however, having learnt spinning attacks and defenses I have found that this way of moving can actually surprise the opponent and unlock options such as spinning backfists, reverse elbow strikes and spinning kicks.

I'll close this post by saying that learning traditional techniques of any style is essential, but when the time comes to defend yourself- do what it takes instead of trying to fit this or that move in somewhere. If you take this approach you'll find that the technique will show up by itself when it is needed.