Nice to see you again, Jochen! Great effect, looks like something organic.
The vdisp 'problem' is however still present. It's all displaced to left and up, at least the ribbons are. Can't see how the holes are done, separete normal displacement?
I've used vdisp to get outcrops on many occasions (trying to avoid a compute terrain/normal), and if using any other than perlin, you get ridges on one side and billows on the other. The best way to get say billows on each side is to mask each side's vdsip by an angle mask, and use 4 vdisp shaders.
But then it's easier to just add one compute terrain/normal