Somewhere in the forum I read that it is not a good thing for the integrated amp??That would be true if the integrated amp had a tube output stage, and output transformers, as that kind of output stage should not be operated without a speaker or equivalent load being connected. Since your integrated amp is solid state, and assuming that it provides preamp outputs that can be connected to the separate power amp (not tape/recording outputs, which would not be volume controlled), no problem as Mofi indicated.
Regards,
-- Al