I only use cad orange in the deepest shadows. For the halftone....where the plane turns away from the light, I use cool paint (almost blue).
It is the overlaping of warm and cool paint from the highlights down into the deepest shadows that allows one to get those soft skin tones.
The following URL has a section that explains this in (I hope) more understandable detail.
http://kcwells.com/technical2.htm