I would think it would slow the cooking process down too. Since you're not able to get heat on both sides of the meat at the same time.
I guess if I were to try it, I would see if I could get the (now removed) membrane sides to face each other. That would leave an air gap between the two racks. But not sure if they would sit like that.
I'd say a better option would be to use a rack. Here's one I found on amazon for $10 that holds 6 rackshttp://tinyurl.com/d59448