Let me clarify for everyone.
Take Bournemouth or any other airport at Sea level, DA is approx 230 ft, ie: 200 above the runway threshhold ht of 30 ft, so if you hold an IR your decision altitude is 230 ft (DH 200ft). If you hold an IMC the recommedation is to add 200 ft, this therefore gives a DA of 430 ft (DH of 400), however this is below the absoute minima of 500 ft, therefore for an IMC holder the DH is 500 ft.
Therefore an IMC holder is not entitled to fly to the same minima as an IR holder.