It has been stated over and again that in Japanese martial arts you move opening, closing across the body, instead of closing/opening front/back like you demonstrated in your video, or an exercises pool noddling.
If you pool noodle without the pool noodle, you end up with a common aikido breathing exercise: hands start low, go up in front of the body, open out to the side above the head and then go back down with arms extended to the sides. I agree that's an example of opening/closing back/front.
Now, if I do the same exercise with only my right arm with most of my weight on my left leg, I would say I am opening and closing across the body. So to me that's a variation of opening/closing back/front.
Do you agree with me up to this point? If not, why not? If so, why do the Japanese prefer the opening/closing across the body over the front/back opening/closing?