what I would like to be able to do is apply a shopping cart discount based on the calculated shipping from UPS or Fedex. The idea is, I build $20 into the price of our products. Any order that has shipping $20 or under gets Free Shipping. Any order that has shipping over $20 pays the full shipping amount, however gets a $20 discount so they aren't overpaying for shipping. Is this at all possible with current cart rules or will it require some new programming?