Actually, last I checked it's a 15% discount with AAA at Earl of Sandwich, so if you're both an AP holder and a AAA member it's better to go with the AAA discount. Disneyland AP holders get a 10% discount at Earl.
Not sure about that. We did the senior discount (it was 15%) for both of our stays in 2011 because the AAA discount was less. Maybe that was different at DLH or The Grand, but at PPH, it was 10% for both stays. And it was 10% in December 2013 at DLH.