My understanding of class 2 nav is that portion of navigation been done out of range of ground nav aids. If that is correct then an aircraft navigating by a GPS driving FMS would never be under class two nav?
Unfortunately, the definitions and rules have not been updated to include GPS as a NAVAID for purposes of navigation Class. Hence, even though GPS/FMS nav is as accurate (or moreso) than VOR/DME nav, pure GPS nav is still Class II.
The definitions, rules, policies, and precedure recommendations need to be updated to the reality of GPS nav.