Originally Posted by
javajunkie
This is just a SWAG on my part, but I'd wager that this special recognition is a combination of minimum MQM - AND - minimum revenue, that makes a magic light go on at DL and *POOF* your a "titanium medallion". And if the average is too low and/or both the mins are not met, you get bupkis...
(beyond the "plain old" - excuse me - "enhanced" PM.)
Great for those that get it. And the rest of us gotta try harder.

I don't know if DL can now calculate revenue of non-DL flights credited to DL SkyMiles, but I doubt if this (i.e., what I said in this sentence) is factored into EP determination.
Like you, I do think EP determination definitely involves revenue scoring (or at least fare code-based scoring) for
DL flights credited to SkyMiles (run predominantly by SkyMiles number). A MQM criteria based on DL-only flights wouldn't shock me either. However, with other airlines such programs aren't usually based on elite-qualifying miles, for it's revenue from own-airline flights tracked by own-airline frequent flyer numbers.