Quote - I have never scene (seen) any of these impact the performance of Poser.

Whilst the actual render time is not affected, having these unwanted material zones in the scene does increase the time spent loading textures, and the memory required to store them.  Whether or not this has a direct impact on the overall render time depends on changes in render settings, and memory usage.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)