This famous paragraph
A flight instructor who is authorized to give such training by the licensing authority of a foreign contracting State to the Convention on International Civil Aviation, and the flight training is given outside the United States.
has had many people running around in circles, and had led to much controversy along the lines of "the only training acceptable towards any FAA license or a rating has to be done by
FAA instructors" (which I have in writing from not a few FAA training outfits in Europe, over the years
), but actually it is crystal clear:
Any instructor legal to do the training in the relevant airspace is just fine.
And obviously if he is not legal to do the training the why are you logging it
