OK I think that perhaps we are overthinking this a little bit, but then again maybe not. Some food for thought: take two diffusing panels and place them as close as possible,or use two fabrics on one panel and shine a light through them. You'll find that adding the second layer of fabric substantially diffuses the light. If howeveryou put one panel in front of the light, and put a second panel 1 foot away you'll have even softer light. The idea that a second layer of diffusion does nothing because the two are basically touching is beyond me. I have to question the idea that the number of layers of diffusion material has no bearing on the quality of light.