Jerry, (how ya doin' by the way)Click on the Johnny Young link and check him out. He's playin' blues on that thing at high velocity. Them guys played on whatever they had handy and figured it out or invented their own way of making it work. I doubt any of them had time to study mandolin theory, they just did it the best way they knew how and that's how new stuff comes to be. They got outta the box and made their own.