Keith- With all due respect, I'm not sure it was covered. Perhaps the first sentence was, but that's kind of an intro to PG's question-

"However, it stated that "Redemption limited to one certificate per passenger per ticket", which makes these much less desirable (as a comparison the Marriott gift certs from Freeride can be combined). I wonder if one could combine the certificate with a coupon."

I too had previously posted the new Freeride AA certs, but had actually missed this potential "problem." PG is a bit more perceptive than I.