A friend faced this very situation when changing types, with the TRTO insisting he needed a vaild ir to commence training. Prospect of wasting £1500 on an mep/ir or hiring a sim and examiner to renew his previous types ir did not appeal.
After a phone call to the CAA, they directed him to the paragraph in Lasors, which mirrors the JAR text quoted above. He promptly put this in front of the TRTO who changed their minds quite rapidly.
Moral of the story, do your own research, and TRTO's, TRE's etc dont always know everything, and will quite happily trot out old wives tales and urban myths till corrected.