Been thinking about the old trick of touching leather to tell if it's real

Read about these AI programs that can't spot other AI programs, and all I could think was — we bookbinders have the opposite problem. You hand me a book and I can tell you in one pass of the thumb whether it was stitched by a person or glued by a machine. The machine stuff is always too clean. Feels like there's a lesson in there about craft leaving fingerprints, even when you're trying to hide them. Or maybe I'm just getting philosophical at six o'clock on a Friday.