deefer dog:
If ever there was a topic that needed a clear and unambiguous explanation and training material, this for sure must be one. Jesus, I don't even understand the naming conventions associated with RNP, but I'm still permitted to fly the approaches!
I can only speak for the U.S. The training, avionics familiarity, simulator time, and line qualifications makes any pilot quite conversant in all aspects of RNP AR. And, the RNP AR IAPs are a separate database the Jeppesen, etc, will not provide for the aircraft until the requirements are met. The FAA is very insistent that all the squares be filled it correctly.