What PP said. I made one a long time ago (pictures posted here:
http://www.quiltingboard.com/picture...ks-t22344.html)
You do have to assemble the pieced blocks and continue with Y seams. I did put them together into rows and after a while I got quite adept at stopping, back-stitching, then pivoting the assembled blocks so it went together pretty fast once I got rhythm. My pattern had the partial units for top and sides and made the partial units the same fabric as my inner border so the mass of blocks appear to be floating in the quilt.