I am about to attempt a two fabric bargello, using an ombre and a bright fabric. The pattern that I have, is for a throw. I want to create a queen sized quilt. I have been thinking about the construction a lot and I admit that I am intimidated. But I truly believe that if you sew the ombre fabrice to the bright fabric to the ombre fabric and then sew the two ombres together to form a huge tube, you should be able to cut the strips and re-sew them forming the bargello. I think it would also be good to sew each strip in the opposite direction as the previous one. And then, at the end (or maybe working in sections) you would make the cut to open the 'tube'.
If anyone has done anything like this, I would love to hear their input because I am very nervous to start this project.