The second video on Beginning Posture is an example of how I teach students about the usefulness of this movement.
This is the type of teaching I typically give to students who want to learn how to use the techniques of Tai Chi.
Students who want to learn for exercise and health will get a slightly different explanation. For health we emphasize on control, balance, posture, alignment etc – basically the stuff that we also need to learn for combat but not as rigorous.
The reason is that if you want to be able to fajing you need to be a lot of precise in your movements. For health you don’t need to be so.
Basically, there’s no one size fits all explanation. I customize the explanation to what the student wants to learn.