I concur with BEagle and must disagree with CaptAirProx. Handling skills and demonstration of decision-making ability can only be checked by practical test whilst instructional skills are better checked by sampling.
Each and every instructor is subject to sampling, irrespective of any internal mechanisms within the RF/FTO, every time he/she submits a candidate for a Skill Test. If an instructor has a lower success rate than his/her colleagues or presents students for test who repeatedly fail a particular part of the Skill Test then this should become obvious to both the FE(PPL) and the instructor’s CFI. Surely this continual sampling is a superior method of monitoring instructional standards when compared to the previous system where during the instructor test the FIE acted as a student and was then ‘taught’ disjointed fragments of a variety of exercises.
As an FE(PPL) I do however believe that the requirement for us to be re-tested as examiners is an improvement upon the old system where the BX examiner authority was revalidated simply by paying a fee. The FIE can set up situations during the dummy Skill Test that call upon us to make a decision as to the outcome of the dummy test and then ensure that the result which each of us awards is consistent with the test standard