You don't learn knife skills at cooking school, because they give you only six onions and no matter how hard you focus on those six onions there are only six, and you're not going to learn as much as when you cut up a hundred.
I was taught how to tie up the loin with a butcher's looping knot and was so excited by the discovery that I went home and practiced. I told Elisa about my achievement. “I tied up everything,” I said. “A leg of lamb, some utensils, a chair. My wife came home, and I tied up her too.” Elisa shook her head. “Get a life,” she said and returned to her task.