Shadows are EVIL!
Okay above you see rough and blurred. The rough pass uses a single sample against the depth buffer. Those bloody pixels are a result of the resolution of the shadow map.
The blurred insanity is a shadow method called PCSS, based on the White Paper, “Integrating Realistic Soft Shadows into Your Game Engine” by Kevin Myers, Randima (Randy) Fernando, & Louis Bavoil. Sadly some of there stuff uses Shader Model 4 so I did my best approximation.
Not happy with either method… pulling my hair out.