It would make sense. (which is why it will never happen) However it would cost Airways a lot of money in new airframes. Money that they are much more interested in spending on revenue creating international flying. To give PSA/PDT more flying they would first need to put more aircraft on property. That is the big problem. Airways can leasing the flying to places like MESA for not much more than it takes for PSA to fly it and have the outside company go out and secure financing for aircraft, and find their own maintenance. The next step is what delta is moving toward in making outside companies pay for their own fuel. Making the independent companies pay for fuel may kill them or it may make then even more enticing to major airlines. All this makes it harder in the short run to justify spending all that money to put more airframes in the hands of wholly owned just to spend less afterward. It is like spending a dollar to save a dime.