Who or what determines “good engineering and good amateur practice,” as applied to the operation of an amateur station in all respects not covered by the Part 97 rules?

Explication

Part 97 deliberately leaves gaps and fills them with the standard of good engineering and good amateur practice, but a standard needs an arbiter. Because the FCC writes, interprets and enforces Part 97, it is the FCC rather than the individual control operator or an outside body that decides what the standard means in a given case.