Delta Airlines has cemented its status as the network U.S. carrier with the worst frequent-flier program, further devaluing its long-cheapened SkyMiles. The leadership of the program or the airline — or perhaps both — doesn’t seem to understand what the loyalty business in 2011 is about. It may be time for a new team at the top.

For more than a year, Delta failed to publish an award redemption chart for most of the world, resulting in lack of transparency about how many miles were really needed for an award ticket. When it finally unveiled a chart this week, the mileage rates on many routes were increased significantly. Many loyal SkyMiles members felt cheated and disrespected, calling Delta’s move a “stunt” in comments posted on FlyerTalk, the largest online travel community…