4.

If you learned Taekwondo right way the technique, which is your ilgiyae, must be under the principles of Samjae and Kang-Yu.
It is reasonable that a technique is under the principles of Samjae and Kang-Yu as far as it is good one. This is not difficult to understand.
You should be able to preoccupy more advantageous position than your opponent and subjugate him with less strength if you use good technique. The principles of Samjae and Kang-Yu tells us just it.