In his book, Above Black: Project Preserve Destiny – Insider Account of Alien Contact and Government Cover-Up (1998), Sherman revealed how he was recruited and trained in a way unknown to his normal ELINT military trainers. The training occurred over the same period as his normal training in ELINT. When he was subsequently assigned to the NSA, Sherman worked on a specially designed computer where he could perform both his normal ELINT work, and also work as an intuitive communicator with EBEs.
This is how Sherman describes, in his 1998 book, the rational for hiding deep black alien related projects under the umbrella of a less classified program:
When someone is assigned to an alien project they are also assigned to the collateral black mission (cover mission). One of the reason for this is if someone were to reveal any alien information, by extension, they would most likely reveal something about the cover project and it would be on this basis that someone would be prosecuted for divulging classified information. (p. IX)
Sherman’s claim of working within a deep black project hidden within a less classified NSA project has been corroborated by the leaked NSA documents. “Sentry Eagle” operates precisely in the way described by Sherman’s account of his time working in two classified programs for the NSA from 1991 to 1994.
