I agree, I only prewash yardage before cutting into it----don't prewash precuts of any size. They will likely fray or shrink and then won't be the correct sizes. The ONLY time I prewashed a charm square was when I worried about bleeding (it was red) so I gently set it in a flat tray of water to soak an hour--then laid flat on a towel to dry. It worked out OK.