What form is being demonstrated? Also what part is the sine wave? The cadence and movement of the form is different from what I have been taught in Shotokan or Taekwondo. Also, there is a jumping knife hand strike in there that I associate with the ITF for some reason.
It was weird seeing the Sine Wave movement for the first time. While I'm sure the physics of whether it adds power or not can be debated, my only thought is it looks very weird as I'm used to Kukki-Taekwondo. It almost reminds me of Taek Kyon or the Taekwondo Dance as done in various demonstrations over the years.
Also, is the loud breathing normal? I noticed the demonstrator was doing it (and I thought it was odd) and then Gen. Choi did it, so I guess it's normal in ITF.
Do those of you doing what you consider to be "genuine ITF Taekwon-do" do both the sine wave movement and the loud exhalations? Just wondering...