I believe that any of the founders of any of the styles, especially if they had been warriors, if presented with a more effective way of doing some part of their system, they would test it and change that part. I really can't fathom why they would not. I'll also bet that's exactly what they did when putting their system together.
As for Kiai, each to his own. I'll use it any way the mood strikes me.
As for Kiai, each to his own. I'll use it any way the mood strikes me.