I think you need to look a little deeper on this one. FCL 900 specifically limits the
privileges of an Instructor Certificate to the giving of instruction for licences issued
in accordance with the EASA regulation.
I read this as meaning an EASA FI Rating only allows instruction to be given
for EASA Licences - ie it does not allow someone to instruct for an
Instruction does, however, occur which would not lead to any EASA
License or Rating issue.
- Someone who is legally allowed to fly, but hasn't done so for over a year
and wants some brush up training.
- A Flying School/Club requiring a Check Out with one of their Instructors
prior to renting an aircraft.
- A Cross-Channel check.
The conundrum is that someone Instructing FAA students also falls in to
above category - but I'm not sure EASA would accept 50 hours of FAA
instruction to count for EASA FI Renewal - theorecticaly that could allow
someone who has done 50 hours of teaching "Circling around a point" (not
even in EASA syllabus) to renew an EASA instructor rating.