There are many, many examples of Chinese martial artists using a push to determine skill level.
What, then, are the differences? We know there are (Even the Chinese have a variety of ways of doing push hands.) Is it just a matter of individual application of Internal Skill? Or is there really a completely different internal skill in Ueshiba's aikido? One that requires a different training regimen to build? (Some of the basics have to be the same, though.)
If a bunch of guys get together that are interested in ki/kokyu/qi/jin skills, everyone will be at different levels, will know some variations that perhaps others in the group don't know, will have different "favorite training methods to develop this stuff best", and so on. That's only natural, right? But the basics will be the same because they must be. Same thing with all these martial arts: Chinese, Japanese, Indonesian, Indian, Thai, Malay, etc...... everyone will have different takes on a lot of things, but the basics are going to be the same; as all those similar demo's should indicate immediately.
Donn Draeger wrote a monograph on "Kiai" in which he mentions how the Chinese are the ones who know the intricacies of Qi so much better than the Japanese. Frankly, I'm not sure that's true anymore.... it's quite possible that Draeger, like so many of us others, simply wasn't shown everything that various teachers knew or could do. One thing for sure, the Japanese didn't treat the Chinese qi demonstrations as "something other than what we do".