. . . if the quilt is worked from both sides of the frame there is a danger that it may be cockled in the middle of the strip worked on. Therefore many good quilters will say that they never allow workers to sit on both sides of the frame and some even run a tacking thread zigzag over the quilt when several are working together, to make sure the three layers are kept in place.
The text is from Traditional Quilting : Its Story and its Practice, by Mavis Fitzrandolph, London : B.T. Batsford Ltd., 1954, page 62. Click here to read the book online, or download it free, from the Internet Archive.
artwork by Joanne Stanbridge 2014