I don't have any answers But this dumb question this time:
My edge meshes doesn't blur. They are alphablend mode and set to transparent. here is screen from Goodwood, and then a screen from Brands Hatch.
Seems that it was because shader was ksperpixel_AT, and it probably doesn't go with alphablend mode because it is AT, changed to simple ksperpixel and it seems better. It is still a bit weird, but I guess because UV is a little bit overstretched.