I think you have to remember that the old masters, probably had a few tools that they made themselves. They no doubt learned to use what they had, and relyed on learning how to get the most out of the tools they had, rather than trying to generate the perfect tool for each application.
An old guy I was introduced to years ago, started carving longrifles after practicing on old table leafs he bought at second hand stores. His first project was a carved lintel to go above his front door. It turned out so well that his wife made him make one for every door in the house. He said he could carve one start, to finish, in about five hours. His carved longrifles looked authentic, not perfect. And at a time when the norm in newly built longrifles was to do the carving in very high relief, rather than the more authentic lower relief that actually fools the eye, he accomplished the latter like the old masters. Practice, practice, practice.
Hungry Horse