Originally Posted by
tismfu
My spouse is CK, I am not. We have the same address in the system (not an AA hub) but his routings almost always start from MCO while mine from DFW. My spend with AA is more than his. I think AA’s systems are smart enough to determine that I am hub captive and he is not, hence no CK for me :/
That's an interesting thought. I would be quite surprised, though, if the algorithm took specific routings into account in the way you're describing. Perhaps high premium route bookings like JFK-LHR are taken into account somehow. Also, remember that getting CK over EP is not purely about having higher spend... it's believed to be more about profitability (though clearly some degree of spend must be there for members nominated via this pathway).
I'd be curious whether your spouse's fares are more "profitable" (higher cents per mile) or are higher fare class bookings on average compared to yours. It's been speculated that full fare tickets are somehow more heavily weighted and that high cost per mile (while not a perfect measure of profitability) is taken into account.