Rosemary, I've also thought about this subject. Certainly the accepted current tread is for the quilting to really steal the show when it comes to show quality quilts. Not to say that the piecing skills or designs aren't valued, but a winning quilt now has to be stupendous in both areas, or at the least, in the quilting area. The video on the Daily blog with the quilts from Road to California shows this on many of the quilts. Isn't that Lord of the Rings quilting something ?!
Quilts of long ago, however, had quilting to hold it together--the quilting was a more subtle design element and there for a purpose, but not meant to be the star of the show like now.
I love all the breathtaking designs, the shine, the artistry of the winning show quilts. But I don't think you'd want to sleep underneath one---I imagine it would feel like corrugated cardboard.
So, at least in my perhaps over simplistic mind, there is magnificent quilting for show, wall or art quilts, and less dense quilting meant to be pretty but not so dominant for our bed quilts that we want to be cozy.