One place I worked we used a lot of Reynolds "Jack Taylor" oversized tandem blades. We got one where they tapered the wrong end, so the top was too thin, not strong enough, but the bottom was so thick it was almost a solid bar, just a little hole down the middle. You could still see where they stamped REYNOLDS BUTTED, which is supposed to be near the top but it was near the bottom, all scrunched up from the swaging - hilarious! Wish I'd taken a picture but I was too poor back then to afford film or developing.