Nice question...I just started Diving in June of 2009 and completed my Master Diver Cert in January. 8 months of classes and diving in my opinion does not make someone a Master Diver...50 dives does not make someone a Master Diver.
I believe the base I developed through the Specialty Courses was a must. There was definately something I pulled from the text and instructors that I would not have thought ask someone I was diving with and the person I would probably be diving with may be really experienced but that doesn’t mean he/she is a teacher.
So I guess my answer is both are needed to make a well rounded, skilled diver.