It's a paper theory because of the reasons stated here. There are plenty of pilots out there who are willing to work for less, so the solution hasn't had a chance to be attempted. However, the lower pay due to scope is real. Ask the guys and gals at Mesa. I really hope they come out on top when contract time rolls around.
Based on past instances, unions have fought the airlines (mainly on safety issues like duty times and aircraft equipment) and won. An airline doesn't last long if pilots aren't willing to fly. Executives won't be getting huge bonuses if no money is coming in (actually, I think I've already been proven wrong on that one). The bad thing is that there are too many people out there that will jump into the seat for less. This is what I don't understand. Everybody is so busy trying to have a leg up that they're willing to cut everyone else's throats to do so. There isn't a lot of upward movement right now, and there likely won't be for a while. Why shouldn't you expect (and demand) what you deserve while you're waiting for that move?
Maybe we should change the name to (PFASTHLTIST) Paying For Airline-Specific Training and Hiring at Lower-Than-Industry-Standard Times. Once you hold the respective rating that you need for a job (Comm, ATP, CFI, whatever) you should not have to pay for training specific to the job you're doing. Like any other industry, you should be hired based on your experience and ability, after hired they should at least be paying for any training needed above and beyond your qualifications. The guy at McDonalds doesn't pay to learn how to use the fryer...