Make sure to do the math on a few representative tickets. If you'll earn the same or more miles through the AS program, even with the reduced earning charts - by all means, go for it if you don't care about Comfort+ seating.

A couple random thoughts:

- AS will eventually end their partnership with DL. I believe the rumored contract end date I last heard was 2016, and I'd be shocked if it gets renewed given the current tensions: it wouldn't surprise me if both airlines announce the partnership end game later this year.

- AS miles expire after two years, so you need to pay attention to keeping them active.

- MVP Gold status is not very helpful when flying DL metal - most of the benefits have been reduced as part of the breakup, and they were never very high on the food chain to begin with. If you care about Comfort+ - particularly for international flights - this could be the dealbreaker.

- AS has some great partners you can earn on if you travel internationally; it's a great opportunity to broaden your horizons. The best way to combat DL program devaluations is to start giving your money to competitors with a better onboard product, and AS makes that an easy proposition... hi Cathay and Emirates.

Even with being essentially a nobody on AS these days with DL status (not even a free checked bag!), I've started booking AS flights when possible to get the higher mileage credit vs. an equivalently priced DL flight. Anything they fly is short enough where I don't really need the upgrade, and I really like their onboard catering (Tom Douglas meals and local Seattle booze from Sun Liquor distillery) and seating (fortunately DL still grants you preferred seating) in Y. The occasional upgrade is just a bonus if it happens.

Long story short I'm still crediting to DL, but I've been dabbling in flying the Eskimo, and I'm only a few more devaluations away from AS making sense as my primary program someday...