So, when you say clamping makes a huge difference... what kind of clamps are you using? I found that without proper pressure, my signatures always shift around when I start sewing. It's frustrating because then the whole book ends up crooked. Do you clamp each signature individually or stack them all together? I used to skip clamping too, but now I see it's worth the extra minute. The alignment is just so much better when everything is held tight.