As I understand it, the short answer is 'yes'.

When using indirect lighting, things like IBL and AO are completely unnecessary and will drastically increase render times when used with indirect lighting, so disable any IBL lights in your scene and ensure that AO is turned off for any remaining lights.

Another tip: transmapped hair really slows things down. In the 'properties' tab, unchecking 'visible in raytracing' will speed things up (the hair + shadows still render OK).

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Windows 10 x64 Pro - Intel Xeon E5450 @ 3.00GHz (x2)

PoserPro 11 - Units: Metres

Adobe CC 2017