Yields have been seen as the problem at FAT in the past for most majors. There is a growing base of small and midsized businesses but few large employers in the area willing to pay high Y and F fares. The smaller firms watch their travel budgets, but still have to travel. They just have a hard time with $500RTs to LAX, etc. Driving makes more sense financially. But it seems the days of high fare travel are gone in a lot of regions.
If yields are a problem for the majors, but the population and business base is growing, that makes a market more attractive for Southwest. Fresno should definitely keep campaigning hard, and retaining Mike Boyd in these matters helps too.
I agree with you about SYR and ROC. However, I think that if JB and AirTran continue to increase services there, it also reduces the opportunities for WN. And I tend to disagree with many about the fate of US. While the company will contract, I think it falls into the area of too big to be allowed to fail (a la Chrysler). No other airline is in the position to replace US's service in the east.
US will be allowed to fail (after the election), and the other network carriers will pick up whatever pieces are desirable (IMO, the PHL and CLT hubs, and DCA/ LGA/ BOS). NW is weak along the whole East Coast, UA is weak in the Southeast, and AA wants a DCA/ LGA/ BOS shuttle. (That's why they've started their ERJ shuttle on the route, they think they can start bleeding US people with their FF miles, and prep for an eventual US bankruptcy). The East Coast will do just fine without US, much as we hate to see such a good airline go. And the low-fares will be able to expand, with good loads and yields right out of the starting gate.
Need a new airline paint scheme? Better call Saul! (Bass that is)