They're a drain on resources and money publishers desperately need to keep print operations afloat. (accrispin.blogspot.ru)
The «stitching» is commonly done with metal staples in commercial printing operations. (owlcation.com)
I doubt that they are any more accurate than other printing operations, and even today we find errors in official versions of legislation, where scrutiny and process are presumably most tightly controlled. (slaw.ca)