Update: I stitched every book head-to-tail for 4 years before a customer in Raleigh flipped one open
I was at the monthly bindery meetup in Raleigh back in March and a woman named Doris handed me back a rebind I did for her, opened it to the middle, and asked why the pages fanned out so stiff. Turns out I had been running my kettle stitches the wrong direction on every book since I started, so the signatures pulled against each other instead of with each other. She showed me her own notebook from 1998 and the spine just fell open flat, and mine creaked like a screen door. Anyone else have a basic step they got wrong for way too long and only caught it because someone else opened your work?