The "non" in "non-fiction"

In the CJR, Samuel G Freedman asks for a little less exercising of the imagination in non-fiction:

Fiction isn’t the spackle you use to fill in the cracks of your research. Fiction and nonfiction make fundamentally different compacts with a reader and are held to fundamentally different standards. In return for the freedom to invent, fiction must reach a benchmark of psychological truth. In return for the allegiance to factuality, nonfiction can present what may seem implausible and tell a reader, But that’s what really happened. When John Berendt confessed to inserting fictional material into Midnight in the Garden of Good and Evil, he tried to shrug off the violation by saying he was merely “rounding the corners” of the narrative, to make it as shapely as possible. But writing nonfiction means having to live with corners that refuse to be rounded.
Since the James Frey scandal erupted, I have yet to hear anyone in publishing offer a persuasive explanation for why writing a biography of oneself or one’s family should be held to less of a standard of factuality than, say, Ron Chernow is when he writes a biography of Alexander Hamilton. I have yet to hear a persuasive argument for why conducting scrupulous research for a memoir or family history should be considered antithetical to high literary achievement. The publishing industry has too much money to gain by holding to the debauched status quo, searching for the next Frey-style blockbuster, willfully forgetting the bit of wisdom that says, If it’s too good to be true, it probably is.