Well, this has been a disappointing read.
I've flown 6 TATL and 2 TPAC in the last 6 months on DL with the hope that I would figure out the secret incantation to start getting upgrades only to read this thread and realize I've been flying the wrong airline this whole time.
All of these flights are for business, but it's my company, and I can't justify spending Delta YBM-fare prices with the amount the rest of my team and I travel.
I did SFO-FCO last week and it cost me $1200 for T, M was around 3k and Y at 4 so I don't understand folks saying upgradeable fares are only slightly higher.