Shorting stocks during a bubble is a great way to learn about bounded upside and unbounded downside. I guess in some sense a valuable learning experience is "taking advantage."
EDIT: Let me rephrase. I think it's silly to call Facebook "old and mature" when it IPO'd 18 months ago. It makes it sound like you would have had a shorting strategy for it some time ago, perhaps 18 months ago - which might have failed miserably - but now would sweep that under the rug, pretending to have never had it.
Of course, we can all be clairvoyant if we sweep our losses (FB is up 27% versus IPO opening price) under the rug. Shorting as a strategy works wonders if you ignore when it doesn't.
Those are the exceptions to the rule. How many planes and routes do you need to even merit consideration at a major airport?
To organically grow, you'd need to find desirable and under served routes between smallish airports, build a loyal following, then maybe you take a risk, borrow money and attempt to move mainstream. Not impossible but it seems like you'd need just tons of money.
Is there much room for value add and innovation? The most obvious area I can think of off the top of my head would be an airline that did all their own security and skipped tsa but I don't know if that's allowed and I think the work would be akin to building your own airports.
Children learn faster because they have to, i.e. they can't get a chocolate bar unless they ask for it. Most adults learning a new language have the luxury of being able to use their native language to survive, and tend to default to the easy option if given the chance, especially if they are learning in a country that doesn't use the language they are learning, in which case they can't use it all the time anyway.
