- There is definite fraud in teaching of the arts
Sham videos of a supposed "tai chi master" pushing someone using only their "chi", never touching them.
I had a friend who was part of a cult in college, and the leader would hold karate demonstrations where he would stop a group of student attackers just with his magic powers. (In that case, I suspect the students being stopped by the magic actually believed it, but it may well also be true for the students of the magical tai chi wizard.)
Pressure points do, however exist—think "hitting your funny bone." And it's possible to press down on the main artery that delivers oxygen to the brain with the thumb, although most people effect this with chokeholds.
In any situation where a product or service is being sold, there is chance of embellishment.