The CD Plane into a neutral 3D space is the only one function who has not the big easy use of the other!
And so between 2 any surfaces with any orientation in the Space!

I have a method without C PLane :)

Make a triangle between the 2 Surfaces Plane
Then Orient / Line Line" / None this triangle on any axe
Then Flat the Triangle on this axe with the Edit Frame
You can now use The Angle Dimension! :)