I didn't know you were not suppose to duplicate. Lordy how does one keep that straight unless you separate all your fabric into two groups and never mix them. I would think it would be an ongoing project and if you were working on anything else that would be hard to do. I've been trying to do a Cathedral window and not duplicate and I've blown it already. I only work putting the color in the windows when we travel so it'll take me a long time to complete.