How to book a cheaper flight (to a hub city)

Arbitrage at work?  This seems to only work with one way flights to hub cities (Dallas-Fort Worth, Atlanta, O'Hare, Salt Lake City, Charlotte), but I've always thought it would be a neat idea to book a connecting flight and hop off at the connection:  How to Beat High Airfares

A nonstop one-way ticket from Des Moines to Dallas/Fort Worth is $375 on American Airlines, for example — more than the $335 Delta will charge you to fly from Miami to Anchorage.

But what happens when you’re interested in flying American from Des Moines to Los Angeles, which hosts a more competitive airport? That flight is only about half the price ($186), despite its being more than double the distance. Now, here’s the trick: American flights from Des Moines to L.A. have a layover in Dallas. If you want to travel to Dallas, the best way to get a reasonable fare is to book the flight to Los Angeles instead, and simply get off the plane at Dallas.