It's not a complete reversal of what Rumsfeld believed in 2003, but it is a reversal of part of what he said.
First off, let's make one thing clear: Rumsfeld's control over the Iraqi political infrastructure ended in May 2003 with the arrival of Paul Bremer. The direct administration of Iraq until 2004 was not Rumsfeld's idea, but State Dept. official Paul Bremer. The two constantly clashed about policy in Iraq, with Rumsfeld arguing that the approach was too heavy handed.
So here's the reversal and lack thereof.
Consistent: Rumsfeld from the beginning called for a hands-off approach in Iraq. He believed that the US could not implant its system and that the Iraqis must be allowed to form their own form of government. He envisioned toppling Saddam and leaving by the end of summer 2003.
Flip Flop: Rumsfeld never said that American-style democracy was realistic, but he believed that democracy itself in Iraq was realistic. Rumsfeld never imagined a United States of Iraq, but he did imagine that the Iraqis would form democratic political parties and govern themselves effectively after Saddam Hussein, which turned out to be disastrously false. When Iraqis were looting Baghdad, Rumsfeld called it "catastrophic success" and claimed that "freedom's untidy." In his memoirs he compared the looting of Iraq to the chaos in Germany after WWII.
Ultimately, Rumsfeld's and Bremer's plans were both given the chance to fail. At this point in time Rumsfeld's revisionism won't do any good. His counterpart Paul Bremer still insists that Iraq is better off today than it was on March 18, 2003.
I guess I'll leave it with this question: Was democracy ever a possible outcome in Iraq? If yes, how could it have been done? If no, where do we go from here if we abandon democracy in Iraq?