Political arithmetic is always suspect, and one should always examine carefully the claims of those seeking votes. Smart observers have learned to distinguish between the claims of political candidates and their advisers and proposals that have been evaluated by independent scorekeepers such as the Congressional Budget Office (CBO). This principle was aptly illustrated by the “budget analysis” Mitt Romney’s chief economic adviser, Glenn Hubbard, recently put forward. In a Wall Street Journal op-ed this week, Hubbard constructs a budget plan that he imagines President Obama might propose someday, engages in a set of his own extrapolations and then makes assertions about it.
Summers, Lawrence H. "Romney’s Fiscal Fantasy Plan." Washington Post, April 26, 2012.