I doubt it would do anything...other than make your ride twice as rough. If the springs have the same arch, and you double them - you get the same amount of lift as 1 add-a-leaf (ok, maybe a tiny more because the arch is held up better), another leaf thickness of lift, and a whole lot of rough ride. Not a good plan in my opinion. ORD zero-rate and add-a-leaf wouldn't be too bad if you were desperate.