How long does dried pasta last?

In his book, "What to Cook When You Think There's Nothing in the House to Eat" (Harper), Arthur Schwartz writes that "pasta will last a very long time - years - on the shelf, but it doesn't last forever. Very old pasta will be so dry that even when it boils to an edible texture it becomes brittle and has a dead flavor - not the nutty grain flavor it should." When I spoke to the Italian-food authority, he told me that, in fact, he had just purchased a package of imported pasta whose "best if used by" date was May 2009 (it had been on sale) and that when he cooked it, it fell apart. So, those factory-stamped dates are worth paying attention to. In their absence, Schwartz said, two years from the purchase date is a good rule of thumb.