Originally Posted by
FullFare
This has been a chronic rub for me over the past years. Now that the US airline industry has been reduced to an oligopoly of 3 legacy carriers (UA,AA,DL), I have had to compare them intensively, point for point.
FWIW, UA is worse, and DL never was even playing triple A ball on this anyway (for their SWU's).
You might want to have a look at DL Global Upgrade Certificates (GUCs) which replaced SWUs a ~year and a half ago. They are valid with any fare class execpt Basic Economy (E) and if upgrade inventory isn't available they go into empty seats at the gate. They can be used selectively on AF & KL-metal, too.