I agree - if you want to learn to apply it to something effectively, then you have to practice applying it to that.
I think the issue here is defining "applied skill". If it means learning how to apply my bodily mass with great efficiency of movement and maximization of force generation and then delivery (as in why I showed the clip of muhammad ali) - then you could readily see that "applied skill" using an axe while splitting wood, or while hoeing the ground.
The proof could be in how efficient they are, how much energy expended in their movements, and possibly in how much force they can generate, and deliver. This doesn't prove combative ability, and I haven't made claims that it does.
I'm arguing that Chinese arts have an organized system that provides expedience in developing Nei Gong.
Competent ring fighters - yes.
If your goal is ring fighting - then you need to spend effort on tailoring your training toward those limitations.
This is a qualm you might have with TCMA in general, but most people I know practicing TCMA aren't doing it with interest to fight or win in rings - whereas most I know doing MMA, muay thai, etc have that as their primary motivation.
I really don't understand what you expect a video of someone hitting a bag to do for you.
Anyway - William CC Chen is seen hitting a bag for a couple seconds at the beginning and later in this clip : http://www.youtube.com/watch?v=m4tMo8gE2Yk
He mentions teaching Nei Gong, and visually looks quite efficient in movements despite being very old (maybe 80s?).
He also mentions in an interview that he never spent time in his life focusing on the health aspects of the art - and I believe I read that he churned out a couple decent ring fighters.
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I think more relevant to testing would be videos of research that can show body coordination and plug into muscle groups to compare efficiency. But who would even fund such research is the biggest question, issue, and challenge I see. Not much money on the table for "alternative" therapies/healing modalities, and even less that I'm aware of for longer term mutli-faceted studies it would demand.
Example 1) http://www.youtube.com/watch?v=HN88QIsMHqA If this had more funding behind it - you could add in more variables, account for activated muscle tissues, test for muscle efficiency/o2 expenditure, and other things.
In the end though, All that probably wouldn't prove any single Nei Gong developing practice is better than another - due to intrinsic uncontrollable variables from person to person.
What research might be able to show is that certain nei gong practices (controlled) consistently (if you had large enough samples of people doing consistent interval tests bi-monthly while practicing those nei-gong developing methods) could achieve results in bodily power generation, possibly in power delivery (with sensors on a bag) in relation to bodily efficiency.
Example 2) Less scientific, but an example for you because you wanted people punching bags.
http://www.youtube.com/watch?v=uVkjj...tu.be&t=17m12s
I didn't claim western boxing proves anything.
I mentioned that Muhammad Ali looked to have fair amount of physical efficiency in movement and balance that could be attributed to some level of internal ability.
And I didn't say Chinese do anything best - I said they have organized methods to develop Nei Gong.
That would mean that these practices to develop Nei Gong could be taught Without learning any fighting (ex. Boxing in a Ring) and thus can have greater application to the myriad of things we do in our daily lives.
My primary goal in practice is health benefit, so that's what I emphasize. If I had more free time, I would spend it doing volunteer work, finishing home renovations, traveling, or other things I don't get time to do- then if that were all done, I would spend extra time to train combative application and practice.
Well - IMO there are tangible and less tangible benefits of it.
I don't claim to know the ultimate definition of Nei Gong, and certainly different schools/teachers definitions have variation.
We can't control people's practices and beliefs, and any emphasis they place on their daily activities.
America is in a health epidemic - not everyone wants to learn how to apply efficiency of movement to fighting people.
I can understand why you say you are frustrated though - but if you relieve the "TCMA" of having any ego or self - then who cares what others think of "TCMA" as a vague generalized whole? If you can spar, defend yourself, or fight in a ring - then be the example you wish to see/others to see.