I guess the next move is to buy a 75 gc for 50 using amex. Then make 3 purchases totaling 50 each using one gapcash and 25 from the gc. That would be another 66 percent off. If you have more amex/gapcash, rinse repeat. Won't be as good as today's sale, but more selection, and still decent.
Eta: gapcash is 25 off 50 full priced items.