yelling at the students, sometimes popping them in the legs with a small stick. they really dig down and push the students, but i feel now that this is the way they help the student find their full potential.
Yeah, this seems to be the norm in China. When my coach first started teaching here, he was kind of like that. He had a stick and gave one of the kids a light smack. I was like Of course, then we had to explain to him that that's not legal here

In regards to positive reenforcment, my old coach said the key was to just point out something good the student is doing with every criticism. Like "Nice expresion, but you need to work on your posture."