Why donít bus drivers use shortcuts?

Cabbies use shortcuts and when he drives in Chicago, Austan Goolsbee uses them too. Yet bus drivers just sit in gridlock:

You might think at first that the problem is that the drivers aren’t paid enough to strategize. But Chicago bus drivers are the seventh-highest paid in the nation; full-timers earned more than $23 an hour, according to a November 2004 survey. The problem may have to do not with how much they are paid, but how they are paid. At least, that’s the implication of a new study of Chilean bus drivers by Ryan Johnson and David Reiley of the University of Arizona and Juan Carlos MuÃ?oz of Pontificia Universidad CatÃ?lica de Chile. Companies in Chile pay bus drivers one of two ways: either by the hour or by the passenger. Paying by the passenger leads to significantly shorter delays. Give them incentives, and drivers start acting like regular people do. They take shortcuts when the traffic is bad. They take shorter meal breaks and bathroom breaks. They want to get on the road and pick up more passengers as quickly as they can. In short, their productivity increases. They also create new markets. At the bus stops in Chile, people known as sapos (frogs) literally hop on and off the buses that arrive, gathering information on how many people are traveling and telling the driver how many people were on the previous bus and how many minutes ago it sat at the station. Drivers pay the sapos for the information because it helps them improve their performance. Not everything about incentive pay is perfect, of course. When bus drivers start moving from place to place more quickly, they get in more accidents (just like the rest of us). Some passengers also complain that the rides make them nauseated because the drivers stomp on the gas as soon as the last passenger gets on the bus. Yet when given the choice, people overwhelmingly choose the bus companies that get them where they’re going on time. More than 95 percent of the routes in Santiago use incentive pay.

Article here; via Dan Klein of EconJournalWatch.