Bk4 Differential grind angle

[Tanker 1/66]

I remember seeing a video possibly with Mr.E Or reading a thread about the angle changing as the edge transitioned to the sweet spot. I have looked everywhere and can't find it. Help!!!!

 

[Tanker 1/66]

Found it!!!!
http://www.bladeforums.com/threads/sharpening-the-machax-on-the-wicked-edge.950799/#post-10808205