Thanks again m1469! I have been thinking a lot about all that... and I tried to sit the right way and it feels a lot better that the way I was sitting before... I'm not sure if I'm doing everything right but... I hope....Oh that link that you posted... it kinda doesn't want to work :- it says it can't find that site... but I'll try to find it somehow!
Well, ever since I brought it up with you, and ever since my whole perspective has been changing on my studio, I'm being a better enforcer with each of my students. Which has also meant that my own thoughts on it and how to "teach" it are becoming more clear. Perhaps I can make a video for you sometime soon.