It also turns out I was never in Windows Mixed Reality For SteamVR Beta ( not sure if that matters anymore with updates)
The script settings I had was keeping Motion Re projection turned off by two dash lines.
Example:
Left Image is Disabled Motion Reprojection, Right image is Enabled Script (Here is Script Settings I'm using driver.zip )
I clicked on the link @whitav8 (Dave) provided and recopied the Motion Reprojection always enabled Script.
Also "RenderTargetScale" : 2.0 ( I would have to retest this setting back to 1.0 to see the difference)
By having Motion Reprojection always enabled, I comfortably went from SteamVR SS 1.3 to 1.6 with Shadows Low to Insane.
For some reason in VR I don't care too much about Insane Shadows and for performance I reverted back to Low. (Even though Low Shadows creates a occasional horrible Flicker on the Wings of certain Planes.. and any other shadow settings makes shadows pop in and out all over scenery..)
I haven't done too much settings adjustments, but the point is that having Motion Reprojection enabled is absolutely a game changer.
Phil, have you been successfully flying with Motion Reprojection since this Forum started?