If you digitize books can you throw them away?

The Baylor University Libraries Digital Collections Blog has an interesting post that discusses the question of whether it is responsible to discard the print copies of books etc. after you have digitized them and saved them in digital format. The discussion brings up Double Fold: Libraries and the Assault on Paper, the Nicholson Baker book that is a must-read for every library & info science student. Some librarians do not agree with Baker's opinion that it was shortsighted for libraries to discard newspapers after they had been converted to microfilm, but the post's author agrees. As he explains, "what about the things we can’t predict? What if the next generation of computers is so different from what we’re used to today that the very idea of digital files changes completely? What if a specialized virus destroys every TIFF file in creation?...The best answer is to do what people have done since 200 BC: go back to the paper versions. That’s why we counsel our partners to use the process of digitizing materials to serve as a catalyst for rehousing materials in archival storage if they’re not stored that way already. That’s why we urge conservation of fragile materials before they arrive at our center. That’s why we never tell them it’s safe to throw something away just because it’s been scanned, cataloged and placed in a digital collection."
This opinion is shared by a British Library study that says "In summary, digital is not generally viewed as a suitable long-term preservation archival surrogate for print. It is currently regarded more as an access medium. As a preservation medium, digital was generally seen as unstable, experimental, immature, unproven on a mass scale and unreliable in the long term."