The nail in the British coffin comes from cost and not from any JAA regulation.
Surely you don't believe that someone that has an ICAO instrument rating should have to complete the same 50 hour flight course as someone that hasn't got a rating already??
If so, maybe the CAA should give checkrides at Heathrow airport to US, Australian, South African etc with non JAA instrument tickets.
Paco, if you have a CAA fixed wing instrument then I believe under JAA it is a 10 hour add-on for the helicopter one.