I always get a kick out of seeing how startled individuals outside of music studies are when they learn that the vast majority of music majors in America graduate with little, or more often, no skills in the primary creative processes of improvisation and composition, nor in the African American musical heritage that is arguably America’s primary cultural contribution to the world.
Questions often arise about the validity and wisdom of reading channeled materials. Is there an unimpeachable source? Sorry to say that there is no definitive answer. The materials that I have encountered run the gamut from extraordinarily helpful to not worth bothering with. How is one to decide?