lol...no, I'm not known for my logic. I was really playing in terms of what I was seeing in the renders.

In the animated gif above (slightly lost a little of the smoothness in the terminator, but it still tells a story):

1. bb's terminator softening nodes as plugged into the diffuse as originally suggested.
2. same nodes minus the blender and now plugged into the Diffuse Reflectivity control adding redness.
3. the terminator softeners plugged into the GC control and Tint control (as I had them in my first render)

I find the terminator line too sharp still in 1, but 2 and 3 are a lot nicer.
Notice how the terminator line creeps across as the sequence progresses. I like 2 as a happy medium overall, although I liked the slightly deeper redness of my first attempt.

 

PoserPro2014(Sr4), Win7 x64, display units set to inches.

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