Julian,
I wrote to the CAA to get them to confirm this, and they wrote back and said you can only operate under IFR or in accordance with IFR in UNCONTROLLED airspace on an ICAO licence with IR, but that they WILL issue IMC rating....for the 64 quid fee of course....allowing IFR ops in up to class D.
This confusion stemmed from the CAA website which used to say "has the same privileges as the IMC rating", but was later ammended to "outside controlled airspace only".
Yea, bollocks I know......
Cu
EA