If you allow me, what you mentioned here is all about the core, which should controls the limbs, not the other way around and the rotation of the core is meant to facilitate the movement of the limbs and the position of the head & thus the breathing. The head will lead the direction of the core without the arms - I don't think the lead arm can or should do that. The head and the core (the shoulders & chest) should be activated first before the arms do anything. Same goes with the kicks - the glutes should be the motor, not the knees or the feet. You might swim well due to years of practice & habits but you sure need help to understand the true mechanism involved here.