Have you ever read a recipe that says, a pinch of this and a large spoonful of that? That is how old recipes used to be before everyone had a scale and cups, ounces, and the metric system even existed. It's a lot easier now days. In culinary school, after measuring salt, sugar and flour over and over, I got pretty good as guessing how much I needed. That is how older recipes worked, the person who wrote the recipe knew from repeated making of the recipe how much worked each time. However there are times I still find myself in a "pinch" wanting to make a dessert but not having access to proper measuring equipment. Believe it or not, not every kitchen in France is as well equipped for pastry making as mine is. And while I can pretty much eyeball a teaspoon of salt without an actual teaspoon still, other measures are not as easy for me now.