Not possitive, but I'm suspect the highend shader has a "surface luminance" utility attached.
From the Maya help files (which explains it better than I can):
"Surface Luminance is a utility node that tells you the luminance (brightness) of a point on a surface as it is being rendered. This luminance takes into account all the light sources shining on the object, and the angle at which they shine on the object. It does not take into account the specular properties of the object itself, such as 'hotspots'.
You can use this node to make interesting shaders that change based on the light in the environment.
Example: Say you are modelling a windscreen of a car, made of a special glass that becomes darker (more opaque) in bright light. To do this, create a Surface Luminance node, and connect its output to all three input channels of a Reverse node. Then connect the output of the Reverse node to the Transparency attribute of a shader.
In the table below, important attributes have their names listed in bold in the description column."
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