Anisotropic roughness mapping issue/question

[Esben Oxholm]

Hi there.

I'm trying to use a map to drive the x-roughness of an anisotropic material.
However, it's like that the mapping only affects the roughness if applied to both roughness x and y at the same time. See attached screenshots.

Is this a bug or the way that the material is supposed to behave?
Best,