Yes, still works in Poser 12 Firefly. I simplified the setup a bit by swapping the order of the diffuse nodes and ditching the Abs function.

ETA: Of course, as one would expect, this does *not* work for SuperFly. So, I'll have to figure out how this works in SF, as well (easier, at my guess, which is why I only asked about FF for now) and then, unlike shown here, use two separate root nodes.

-- I'm not mad at you, just Westphalian.