I find it hard to believe that the same person writing that line is going to have the same qualifications as someone actually doing what we imagine the NSA does.
A copy error completely means that the NSA is incapable of doing its job! /s
Obviously, everyone has typos, but this wasn't just a typo (they got the entire paragraph wrong). And it was one of the most important paragraphs in one of the most highly visible documents they've ever released. Can you imagine what would happen to a corporate law firm that, on the eve of signing a billion-dollar real estate deal, accidentally/"accidentally" inserted extra zeroes into every number in the final contract?