The function editor is full of power and mystery and it's depths can be daunting. When knowledge is shared among users like in this thread, it can spur wholly unexpected explorations. I would have never, on my own, discovered the whole 'vector' thing. Or, it can just refresh. I used a lot of displacement when it first came out but subsequent versions' inability to handle displacement made me get used to not using it. It was one of the things I was missing in my quest for craggy, jaggy rocks. I also discovered that some of my material 'mixing' was unnecessary. With some further linking in the function editor I was able to emulate the mix in a single layer. What started out here as a search for 'blur' ended up with a lot of clarity. Life is good.