PA28Bigs,
The CPL course includes a minimum of 10 hours of IMC flight, unless you have an IR. There is no reduction for holding an IMC rating, nor for any other instrument flying. So if you don't have an IMC rating, there is plenty of time on the course to learn everything that needs to be learnt.
However, you have to build 100 hours or so. It makes sense to do a small number of those hours with an instructor to ensure that you don't let too many bad habits creep in. So the IMC rating is, effectively, free. And having the rating will definitely make the CPL easier - the whole of the instrument section of the CPL, except for plotting navaid fixes, was a complete non-event for me. And I'm all for making things easier when possible!
Hope that answers the question. But I have heard a rumour that the amount of IMC stuff on the CPL course is going to be reduced quite dramatically fairly soon.....
FFF
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