I have a Shipping Method for Free Shipping if price is >= $100. "show method if not applicable" is set to no..
I have a shopping cart price rule coupon. 10% discount. Free Shipping is set to No.
When a customer makes a purchase over $100, enters the discount code, and begins the checkout...the option for Free Shipping is still there!
I think it doesn't let the transaction actually happen, but showing it as an option is confusing customers, and causing transactions to be "cancelled".