I agree.  Snarly's EZSkin is not an exact fix.  I have had to go back and examine the images in MatRoom to see localize the problem(s).

Snarly's script does not use the Diffuse or Specular values on the PoserSurface, rather it plugs the nodes into Alt_Diffuse and Alt_Specular.  Anything added to the node arrangement as increased Diffuse_value or Specular_value gets multiplied in the formula.