You will always need some fundamental basis of understanding. You cannot bake a new kind of cake if you do not know what preheating is. I believe that is why they give the PhD example. The bulk of education comes before a PhD. You cannot start with a complex problem and be expected to solve it without acquiring knowledge beforehand.
The most instructive kind of problem solving is solving problems badly and learning why you did a bad job. Do that enough times ina row and they call it a career.
This. But then I have a very hands-on learning style - I cannot learn things by watching (or reading about) others doing it. I have to mess one up myself first.
