Suddenly I was ripped back to the time when I was merely a new beginner. I could hear my teacher ask me "What is the first movement in Taegeuk Il (1) Jang?" It was a trick question of course, as most beginners and advanced students alike would answer "Low Block" wich meant that we would receive a 20 push ups bonus in our training as the real answer was "turning your head to the left". Oh how many push ups I had to perform because of that trick question..
Anyway back in our time the veteran asked why we did not turn our heads and I had to answer that yes we did not turn our heads anymore and I do not teach it either. After 2006 when the Kukkiwon started with the world Poomsae championships they also introduced what was for many a new standard. This new standart changed a number of things in our training, the head turns being one of them. Pre 2006 we did emphasise a turn of the head before the body so we could see our new opponent that we were facing. Post 2006 we de-emphasised the head turn and just turned it along with the body when we turned in Poomsae. The reason for this change? Competition.. We would be deducted points for emphasising head turns so we had to switch to a "natural" head turn (turning the head with the body).
Taegeuk Il (1) Jang with its 18 counts or steps would sure make a loooong line if it was performed in one straight line without turning at all. I am not sure if I could practise it anywhere but outside as I have a shortage of such looong and open rooms. Even if you introduced a turn at the midpoint you would still be going 9 steps forwards before turning and making your way back again..
I think I will let Mabuni (Teacher of at least one Kwan founder and fellow student of Funakoshi who taught many more Kwan founders) sum the turns in forms up as he does so very well:
Kobo Kenpo Karatedo Nyumon by Kenwa Mabuni as translated by Joe Swift:
The meaning of the directions in kata (Poomsae) is not well understood, and frequently mistakes are made in the interpretation of kata (Poomsae) movements. In extreme cases, it is sometimes heard that "this kata (Poomsae) moves in 8 directions so it is designed for fighting 8 opponents" or some such nonsense. I would like to specifically address this issue now.
Looking at the enbusen for Pinan Nidan (Pyung Ahn 2 Hyung), one can see that karate kata (Taekwondo Poomsae) move in all directions, forward and back, left and right. When interpreting kata (Poomsae), 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 (Poomsae) begins to the left that the opponent is always attacking from the left. There are two ways of looking at this:
1 - The (Poomsae) kata is defending against an attack from the left.
2 - Angle to the left against a frontal attack.
At first glance, both of these look alright. However, looking at only number (1), the meaning of the kata becomes narrow, and the kata, which in reality must be applied freely in any situation, becomes awfully meager in its application.
Looking at an actual example, the 5 Pinan kata all start to the left, and then repeat the same series of techniques to the right. Looking at interpretation (1), the opponent must always attack from the left, and while fighting that opponent, another opponent comes from behind so the defender turns to fight that opponent. This type of interpretation is highly unreasonable.
Looking at interpretation number (2) however, the 5 Pinan kata show us that against an attack from the front we can evade either left or right to put ourselves in the most advantageous position to defend ourselves."
Here is a link to the original site where I found this.
So to sum up: Head turns in forms were probably introduced as a result of poor understanding of the applications of forms. No head turns may be Kukkiwon`s attempt to teach us something (like forcing us to consider more advanced applications than the ones they provide).