Bug with Skeletal Mesh Import and Mikk TSpace?

Could there be an import problem with Skeletal Meshes in relation to the Normal Generation Method “Mikk TSpace”?
The following two screenshots show the same mesh with the same material and scene settings. Both have been imported exactly the same (Import Normals & Mikk TSpace), only once as static and once as skeletal.

Static Mesh:

217374-static.jpg

Skeletal Mesh:

217375-skeletal.jpg

I`ve encountered the same issue not long ago. Couldn’t find a solution tho. Would be nice if someone finds one.

Fascinating. I’ve encountered the problem you’re describing in the second image many times with my work. There are two solutions:
Solution 1) In the mesh import settings, set the Normals import setting to ‘Import normals and tangents’. This will import the normals from the source file and not use the Mikk t-space normal compute method.

Solution 2) This is more involved. In your 3D modeling package, either set the renderer to show you the invisible triangles that make up all geometry, or manually triangulate the mesh. The errors you are describing will appear as triangles that follow a zig-zag pattern: /////. rotate the faces so that all triangles follow a slanted pattern instead, like so: //////. this will fix the problem with Mikk t-space normals.

What I want to know is why this happens and if there’s anything to do about fixing it without having to do all that…