I think my theory was flawed I'm 8/22 right now

100% correct

I would assume you get the benefit since you have the card, regardless of whether the card was used to book, but the GIDS doesn't display the breakdown for why you are where you are on the UG list so I couldn't tell you that.

I think the only thing this 'simplifies' is recognizing the fact that there is now even more obfuscation in the upgrade list and process.

I think they should put an R next to your name on gods if you have a reserve card.

I can probably say that this does have some effect. DM on a V fare with applied GUC to itinerary. The domestic leg didn't clear: LGA - ATL. I was #7 out of 45. Unless there were 6 other DMs on GUC higher than V fare on my flight. This flight was today so the Y fare restriction is in effect. No biggie. Short flight.

Corporate GM K class > GM Q class on my upgrade list today.

Why would that be....I thought corporate status was the last tie breaker?

It was a broken fare with Q on the return but his particular segment was K. That might change things.

Having different fare classes on outbound and return doesn't mean it's a broken fare. For example, see this RT fare:

Fare 1: Carrier DL KRVQA0MA ATL to MSP (rules)
Passenger type ADT, round trip fare, booking code K
Covers ATL-MSP (Economy)
$239.07
Fare 2: Carrier DL URVUA0MA MSP to ATL (rules)
Passenger type ADT, round trip fare, booking code U
Covers MSP-ATL (Economy)
$192.56

ATL DL MSP 239.07KRVQA0MA DL ATL 192.56URVUA0MA USD 431.63 END ZP ATL MSP XT 32.37US 8.00ZP 11.20AY 9.00XF ATL4.50 MSP4.50

Regardless, upgrade priority is determined by the fare class of a particular segment. Fare classes of other segments on the itinerary are not relevant.

This will probably make the biggest difference on the east coast shuttle markets and certain other DCA flights.

Saturday flew LGA-DCA and was number 9 / 18 on the list as a Diamond on a Q fare. On the return Sunday May 1st was 2 / 30 on the same Q fare. Finally I got to be ahead of all the corporate Y fares. BTW.. still didn't make the upgrade. Flight was full with media honchos returning from the White House Correspondents' Dinner.

Is this section new? It's the 3rd bullet in the "Improving your Priority" section:

"If all else is equal, Card Members who earned the Medallion Qualification Dollars (MQDs) Waiver by spending at least $25,000 in the current calendar year on their Delta SkyMiles Credit Card from American Express will enjoy higher priority."

So that means that at the same medallion level, fare class, etc without a Reserve card, medallions that qualified using AMEX exemption are ranked above those who qualified with normal MQD spend. That has the potential to be HUGE!

I should hit PM soon again with AMEX spend so i'm looking forward to seeing how the priority changes.

Thanks for the clarification. Ticketing isn't my expertise. This means that corporate status is more than a tiebreaker merely within identical fare class... possibly fare class family like YBM, SHQK, LUTXV or something.

Yes but what about folks who have met the MQD spend, AND hold a Reserve, AND have $25k+ on the Reserve? I think that puts us on the UG list for seat 1P, no?

Doesn't the new DL.com language include something about "fare class families"? Is this a thing, where groups of fare classes make up a family (YBM/SHQK/LUTXV)?

If so, that greatly changes the prior equation on how UG priority is determined. Could mean that a corporate K fare trumps a consumer S fare. And with the removal of Y-class priority, that someone on an M fare trumps full-Y.

Of course, FPAG still trumps all of those.

Yes, the "fare class family" language is suspiciously vague, though my guess is that Delta is currently still segmenting upgrade priority by each individual fare class.

Delta doesn't expressly publish fare class groupings/families, but this breakdown sounds about right based on fare restrictions and how Delta has structured past promotions:

YB: Full fares (with Y being the "rack rate")
MSHQK: Discounted fares
LUTXVE: Deeply discounted fares (with "E" being the rock bottom and most restrictive rate)

You could argue that M belongs in the "Full fares" section, but given that Delta has devalued M by eliminating the 50% MQM bonus and will soon allow mileage upgrades to Delta One on SHQK fares, I think M belongs with the "discounted fares" group.