I have a few of the etude books written by Mr. Herring. He put out many studies but I hardly hear his name mentioned on these forums. I have a book by Bill Knevitt in which he advocates using these studies as endurance studies by repeating the 8 bar sections many times. Has anyone on this forum ever studied with Mr. Herring or someone who studied with him? What was his teaching style? Any particular recomendations on how to get the most out of the books? His books really do not have any suggestions on how to best use them. Thanks!