CO isn't losing high status pax. FT is a skewed demographic. Market research, at least what's published, is that few meaningful pax actually jump ship and those that do, do so because economic conditions force a change over ticket prices or the individual pax shifts travel pattern to routes served better by other carriers or physically moves to a location served better by a carrier.

The choices aren't very real anymore: 1) CO to UA, but so what, they will be one carrier soon enough; 2) DL or 3) AA (but restructuring means cutbacks in flights/routes).

Back in the day when there were 10 real carriers, there was competition. Still exists for those who live at major hubs such as ORD with UACO + AA, but not so much for most people.