Please see the most recent updates in the "Where did the .com name go?" thread. Posts number 16 and 17.
What is the fresnel ramp, why is it necessary and why can't it be viewed in DXTbmp?
Thanks Roman!! The link explains what I was asking about!possibly because the texture isn't squared - https://docs.microsoft.com/en-us/previous-versions/microsoft-esp/cc526975(v=msdn.10)#fresnel-ramp