I would imagine NW is losing money on every flight except for DTW, MSP, and MCO (that one flight is full). But the game is frequency, and NW does not come close to MA (Midwest). All the others were once a day. You can add flights, but if you don't have enough to sway all, you are at risk to lose. I agree with shadowflight that they are just looking for a tax break. But , is it cheaper to operate these flight with a tax break and no PAX, or do something somewhere else?
US Air Exp. will be the first to go around Oct. I imagine. If MA started to CHT, I bet it would quicken the change.
If MA gets the Delta deal, they can weather any storm. NW going to BWI is a play on AirTran, NW to MCI is a play on MA. We'll see.
BTW- Not to be too biased, but we're always full out of MSP to MKE on Skyway. We've done great on that market. We could succeed on MEM and DTW, too.