This is directly from the chief counsel after I asked if FSDOs had any leeway in enforcing the interpretations. It is not a gray area.
"Legal interpretations issued by AGC-200 are binding interpretations of
existing regulations, although they are somewhat fact specific and may not
be directly on point to a particular situation. They are not simply the
opinions of a particular attorney, but rather represent the official legal
position of the FAA's Office of the Chief Counsel, who is tasked with
interpreting the agency's regulations. As such, FSDOs do not have the
latitude to ignore them. Should you get continued pushback from a
particular FSDO, please ask the manager of the FSDO to reach out to his or
her regional counsel or to my office for clarification.
Rebecca MacPherson
Assistant Chief Counsel for International
Law, Legislation and Regulations
AGC-200
Federal Aviation Administration"