I saw the video as well, and want to upgrade my simple "flannel on the wall" to what she had so I can use her technique. She used ceiling tiles as the base for her design wall and covered it with fabric for regular use.
For her sandwiching technique, she pinned enough newspapers to the design wall to cover all area outside of the fabric she was working with. She then pinned her backing fabric over the newspapers (newspapers don't have to completely cover the design wall, you can leave the center free to take advantage of the flannel.) She then spray basted the wrong side of the backing while it hung on the wall. Added batting to the backing on the wall, using pins at the top edge because of the weight, then spray baste the batting. Then finally, put the quilt top on the batting, and smooth it on. She also put a sheet on the floor at the bottom of the design wall so that the overspray would not fall on the floor.
The link where I saw it was on "the Quilt Show" online and I think the video was available free to non-members...can't get to it now to give you the link.