Yep, we all knew this day was inevitable. At least the partnership has lasted this long, especially considering that it started around the beginning of 1999, and Guest Rewards was established in 2000. AGR could've steamrolled this thing a long time ago.
From 2001 to 2006, I redeemed six Coast Starlight round-trip roomette awards (rough total value of $3,000-$6,000) through the AS partnership, mostly on miles earned traveling Amtrak. Of course, I also earned AGR points at the same time thanks to the allowed practice of double-dipping. Needless to say, this gravy train was fabulous while it lasted. R.I.P. ^