I understand the librarians at the Nat'l Archives were suspicious and kept Sandyburger under surveillance.
If that is true, then they had better have made backup copies of every single document that Burglar took (scribbled notes and all), or something is really rotten here.
Choose the rotten door. Documents this classified are not copied without serious reason. The number of copies in existence is carefully recorded. Berg(l)er knew exactly how many copies existed, and he apparently took them all.