Many of BB's older shaders include GC for pre-GC built in Poser users.

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2856674

http://greyscalegorilla.com/blog/2010/11/what-is-linear-workflow-and-how-can-it-help-your-renders-look-better/

...Ummm, monitor calibration and postwork in photoshop are also considerations.

Don't imagine the average Poser user gives it much thought...