Facing forward in kata and then turning to the left, or right, to meet an incoming attack (whatever that might be), makes no sense at all. Yet today this is still being taught to students.
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Throughout the history of karate we have some of the creators of kata informing us….. what they are trying to convey to us, with these opening movements, and the movements throughout the kata.
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Kenwa Mabuni one of the greatest kata exponents of the time stated; “When interpreting kata, one must not get too caught up in these directions. For example, do not fall into the trap of thinking that just because a kata begins to the left that the opponent is always attacking from the left.”
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It is a wide misconception that the angles in which you move when performing kata represent where the enemy is attacking from. This is nonsense.
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The kata is teaching you to move TO that angle in relation to the enemy. It is NOT where they are attacking from.
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The notion of being attacked from the side, or rear, and having the time to defend, defies both common sense and logic.
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Think about it for a moment, imagine there is an attacker to your side and you know he (or she) is there about to attack you. What are you going to do? Stand in your ready stance waiting for him (or her) to attack, so that you can can execute your perfect ‘block’? NO.…. what you will do is face the attacker, and attempt to maintain sufficient distance so that you can decide if you are able to escape, or diffuse the situation verbally, or physically.
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An effective kata application should move us to a position of dominance with an attacker….. which is NOT directly in front of them. Any kata application which gets your to the point in which you are equal with your attacker, is not effective and useful.
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Furthermore, if we limit a technique in kata to a specific defense against an attack from the side (or from the rear, or any other specific position), then we are only able to apply the technique in a very limited set of circumstances.
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An effective kata application should ensure that we have a clear line of attack towards an attacker. If we can put ourselves in a position where our ‘attack-line’ is facing them and the attackers ‘attack-line’ is NOT facing us, then we have created positional dominance. An enormous advantage.
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The applications within kata provide us with the techniques to be applied in many different scenarios, allowing for a greater variety and usage, in comparison to the limited scope of the multiple opponent, attacking from the left, or right, or behind idea. Apply logic and common sense to your applications. 

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“The beauty of a move lies not in its appearance but in the thought behind it.” – Aron Nimzowitsch
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