So now Leo's a moron for stopping tweed amp production about 1960. Because those basic circuits went on to do great things with distortion. Let's think about that a sec. . . Who used distortion very much in 1960? Was it even really a thing in early 1965 when Leo sold Fender to CBS? No not really. Hell Roy Obison was an early Marshall endorser, he wasn't exactly known for distorted guitar sounds. It's possible if Leo had still owned Fender into the 70s he might've revisited those tweed circuits. The man wasn't exactly stupid and he did seem to know what the customers wanted at the time.