I agree with NH. As I understand it, in order to do well at the IR, your instrument flying has to be instinctive so that you can use the extra mental capacity for operating the aircraft. Doing an IMC will give you that extra practice in developing your scan and general instrument handling abilities. However, I guess that the major caveat in all this is to ensure that the IMC training is to a high standard, so that you don't develop bad habits that end up costing you more in the long term to remove.
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