I have not, but i would think that the bottom rack of ribs would braise in the juices of the other two, and get done way quicker, and have a different texture.
i cook with rib racks, to get all done same time i have to stand ribs on end in foil. i don"t add anything but applejuice, & let em slowly steam. works well,everyone says there great. problem is a hole in foil, and space. thinking of putting in a pan and covering then steam. thoughts?