Until this matter is specifically herd in a court of LAW it will be up for interpretation.
Thats why it takes lawyers years of schooling to become one so they can argue even when things seem clear.
Just as McCall's has a lawyer saying what we cant do.
I could find a lawyer to say that we can do anything we want with a quilt pattern other then sell the pattern.
I will go with my original assumption and that is you can not copyright a useful good (ie: clothes, blankets, purses)
They can copyright the pattern it self (the hard paper) so no one could copy and sell that.
If they want to say that its artistic then I would argue that it would have to be able to be separate from the quilt to copyright and that if they do have a copyright on that I would argue that it is implied consent to make their art work since they put out a pattern.
But thats just all hypothetically if I was ever in that situation.
I do know a Lawyer his field is not Copyright but maybe I can give him a call and forward him the copyright stuff and see what he makes of the legal mumbo jumbo.
I wasn't going to bother him but I think I want to know.