Deco Fuse is great for table runner, wall hangings, place mats, totes and bags. It gives a professional crisp finish. I put it next to the fabric and then add the batting. Be careful, the fabric can wrinkle if not fused properly, most times I just sew it in and not fuse it at all.
Do you put it on the quilt/project top?(wrong side of course) Layer it up like normal and quilt thru it? I have never heard of it but it sounds kinda like interfacing. Is it? Learn something new everyday on here.