Hmmm, I for one would appreciate some clarity on this point. I know of a few fellow FIs, themselves holding IRs, who have on the face of it successfully circumvented FCL.915.IRI (which requires applicants for an IRI certificate to have completed a minimum of 800 hours of flight time under IFR of which at least 400 hours shall be in aeroplanes) by simply logging VFR instructional time as IFR. Quite how this was achieved by legitimate means I'm not sure, but I'm assured it was. I very much suspect this is what the OP is referring to. When I enquired how much of the claimed IFR time was gained in cloud (i.e. in IMC), it tended to all go very quiet. Clarity please....
HW