FI1ngfrog
Where does it state that the test only requires a let down to the IMCr minima that you give. The U.K. examiners hand book says that the instrument approach should be a pilot interpreted approach to DA or MDA, and the examiners report section 4.1 says “let down and approach to DH/MDH using pilot interpreted approach”.
The AIP recommends that the holder of an IMCr or IRR should add 200 feet to DH or MDH with an absolute minimum of 500 feet for a precision approach or 600 feet for a non precision approach, but this is only a recommendation, not a legal requirement. I can’t find anything written to say that there is any additional legal restriction to the use of an IRR or IMCr apart from not being allowed to enter class A airspace or take off with a flight visibility below cloud of less than 1500m. Am I missing something ?