I agree that once you have broken cloud using the procedure and become VMC, that the circling minima is appropriate, not the addition of an extra 200 ft for the IMC rating
Consider my base airfield EGNT The AIP gives for a Cat A non-precsion approach NDB/DME 25 an OCH of 371 ft labelled for the procedure. However it also gives a VMC OCH for the total area of 534 ft. If the AIP states that the minima is for a VMC circling procedure for the total area, then no IMC Xs should apply because by definition that minima applies to VMC!
Let us say that an IMC pilot decends to his mdh of 600ft, having broken cloud at 700ft. It would be illogical to expect him to climb back to 734ft, and lose visual contact with the runway and have to execute a MAP.
We teach slow safe cruise/tight bad weather circuit specifically to deal with the bad weather/poor vis. If that can only be done at or near the normal circuit height it kind of defeats the object of the exercise.
http://www.ais.org.uk/aes/pubs/aip/p...s/32NT0810.PDF