why should a Frenchman flying a French aircraft from one small French aerodrome to
another be required to communicate in ICAO Level 6 English when flying IFR?
Just for flying IFR in VMC I would agree, but in IMC talking to an ATC Service I would
prefer a common language is used.
Curiously, the EIR doesn't include such a requirement...
Not so curious:
The EIR specifically excludes Instrument Approaches (except in an emergency).
IAs require comms with ATC - hence everyone listening on the same frequency should
(in my opinion) be able to understand what everyone else says.