Dozens of prominent colleges fill a third or more of their incoming classes through early-decision applications, which prevent comparison shopping for the best financial deal and make it more difficult to get in during the regular admissions cycle.

Source: A college-admissions edge for the wealthy: Early decision
My Comments: My boy got into Cornell on Early Decision.  I absolutely agree that you have to know and work the system a bit.  Thee is definitely a game to be played and a secrecy to the sauce.