The idea was to add various displacement to the filtered object with a slight overlay of colour alterations. And atop that, blend in a blot pattern for more randomness. Didn't come out as expected, but it's way too complex to handle and make basic changes to the setup. Still it's a good source for generating a grunge overlay to objects.
As this one distorts the edges of the filtered object, making an alternative where it fills in the original shape instead -which is more useful for a background texture.