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.
Bill Buford, Heat: An Amateur's Adventures as Kitchen Slave, Line Cook, Pasta-Maker, and Apprentice to a Dante-Quoting Butcher in Tuscany
culinary-school, experience, practice