FlightPathOBN:
Sorry cant agree with that, .52 is very 0.30 specific on approach and RNP 1. there is an option to go to a smaller RNP, but that requires approval from 420...if you are a 3rd party developer.
Could be, I don't know. My comments are about RNP AR IAPs developed by the FAA.
Third-party developers design specials I never see. The very few
public RNP AR the third-party developers have developed are all quite simple at easy (not obstacle or terrain rich) airports. BDL and SAV come to mind.