My own practice follows an empirical approach to Taiji theory and application,
reflecting the teachings of my teacher
Elaborate please. I'm not saying this to be confrontational. I could look it up myself, but that won't guarantee that what I see will be the same thing that you would explain. For example, "Taji application." Are we talking about health application, fighting application, offense application defense application, life application?
What is the empirical approach to Taiji as you understand it. If this isn't clear to other people in the conversation, including me, then we are only left with assumptions which loop us back to the beginning vs moving forward. I'm application heavy, but not so much where I don't see different types of applications. I often use Taiji principles in Jow Ga to help me recognize shifts in the force that is being applied to me. But that may not be the same application that you use, and it may not even be the same type of application that you are referring to.
For me, drop bear, and kung fu wang, we are heavy on fighting application. It's not a secret, everything conversation will eventually "lead to that ocean." Even when explaining types of principles, the question in the background will be "How do you apply that to fighting." If the principle isn't for fighting but for development, then that's something that's not foreign to us. I don't want to speak incorrectly for them, but for as long as I've been on this site, that's pretty much where we live.
So you suggest you can do a thing. You test it under controlled conditions.
The only thing that I don't like about this is that it doesn't take into consideration the size of water that is needed to make dowsing effective. In my opinion it's not a reliable test to figure out if something works. If I were doing that experiment, I would treat it like my martial arts training. I would want to know when it works and when it doesn't work.
My own understanding of water is that it would take more than a bottle of water to have an effect so I wouldn't start with a bottle of water. If it can't detect big sources of underground water, then it's not going to find smaller sources.
If I were going to experiment with it then I would do it this way and then verify with scientific equipment. To me it's like a metal detector. Some metal detectors are sensitive, some only detect certain types of metal. Dowsing would be the same. Was it really intended to find a bottle of water or does it require more water to actually work? I treat martial arts the same way. I have a technique that is said to work. When does it works and when it doesn't work is important.
The people in your video probably never thought it that way. Similarly, some people may mistake a technique to be a strike when it's really a grabbling technique. I'm guilty of that in my own training, but I'm also open minded about my training. Bruce Lee says "Be like water" I say "not every technique or principle is going to fit like water."
Sometimes things have to be applied where they fit.