I just re-drew it with eight ribs. It's not going to save any noticeable weight.
Here's a link to Aileron Differential. There are some image links at the bottom of the page:
http://www.mindspring.com/~cramskill/diffthro.htm
Look at the third diagram on the far right in this image. The holes where the aileron pushrods connect travel 45° each way around the arc of the wheel, but the pushrods travel unequal distances forward and back. There is more forward travel and less rearward travel.