I always wondered how you can be assured that you were indeed getting double butted tubing on bikes when the decal offered no forensic proof that that was indeed true. When straight tubing is dumped consequent to a fire and was used in bikes with very prominent marques and labelled as 531db-- although after Enron I'm very disposed to believe opportunists are indeed creative--, I'm equally drawn to the forensics that is available to substantiate the presence of these straight tubes in good frames. There was always rumors of this practice in the early '70's and that prompted me to stick to someone I trusted, Spence Wolf. In 1976 whilst attending grad school at Simmons College in Boston, I proceeded to try and duplicate a Hetchins frame I had seen in Bicycling magazine's centerfold some 5 years earlier. So I ordered lugs and 531 double butted tubing cut to size. I was shocked at the modest cost. That's when I wondered: am I really getting double butted tubing? Eyeballs don't help, because it's dark in there. But a fitted ball of foam offered a resistance pattern even a dork like me could notice: resistance was greater at the ends because of the butting. Alas, I'm no threat to decent makers, but anyone who's struggled with straightening a good frame by jerryrigging a jig, replacing tubes and such has asked that question about the veracity of makers charging big bucks. Just how widespread was this practice?