Start w/ smart kids w/ relatively affluent parents and any educational strategy succeeds. The kids will do well no matter what. Start w/ less innately intelligent kids w/ uneducated, poor parents and that is where you see what really works. Virtually all studies/articles about unschooling/less schooling approaches and they don't control for this variable.
Show me homeschooling/unschooling/Waldorf/Montessori/Reggio works for poor kids w/ uneducated parents. Until then, I don't give a shit.
I have worked w/ a lot of autodidacts, including a couple better known ones in the software world. They all had professor parents and comfortable upbringings.