Shunter's question related specifically to a situation where the holder of an FAA IR passed the JAA IR exams and just completed the checkride in Switzerland (i.e. did not complete any JAA approved flight training). This is not compliant with JAR-FCL 1.205(a), which states "An applicant for an IR(A) shall have participated in a course of integrated flying training which includes training for the IR(A) (see JAR–FCL 1.165) or shall have completed an approved modular flying training course."
In the case of the holder of an IR issued in accordance with ICAO Annex 1 (e.g. an FAA IR), JAR-FCL 1.016(a) states that he "shall meet all the requirements of JAR–FCL, except that the requirements of course duration, number of lessons and specific training hours may be reduced." i.e approved training is still required but the duration may be reduced.
The scenario that Shunter presented is, therefore, clearly not compliant with JAR-FCL and JAR-FCL 1.015(a)(1) requires mutual recognition only where ratings have been issued "in accordance with the requirements of JAR–FCL and associated procedures".
Now, what part of my response to Shunter's question is factually incorrect or not supported by JAR-FCL 1?