One thing I'd point out is that the two anecdotes you used would be considered discussions about how to do internal strength correctly, but they're both refined discussions, in a sense, in that they assume qi and jin are present in a legitimate way already.
The current discussion about the Chinese and Japanese doing things differently is about like suggesting that electrical engineering is done differently in China and Japan and Japan has left out things they don't need, have added some important contributions the Chinese don't know about, and so on. I.e., it's really a sort of silly argument if you know something about electrical theory, but for people who have no idea about electrical theory it's not hard to convince them that there is a difference between Japanese and Chinese electrical theory if you've set yourself up as an expert with legitimate knowledge.
Me, I go to legitimate experts whenever I can to get things checked out... and I've recommended that people do the same thing. Of course, if legitimate experts aren't good enough to judge you, I can see the problem.
You've missed the entire argument. No one said Chinese and Japanes IP is based on different theory or Japan didn't get the basic theory from China. 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. Therefore if you are suggesting that it is except-able to move opening/closing front/back other than just training (and you really shouldn't work on that much) then you are not teaching them how to move correctly for a Japanese art and should therefore find someone that knows how to move properly for a Japanese art to teach you what to do.