The displacement as implemented in the physical node was behaving weird ... wrong ... uspidebackwards? It's really hard to explain. Let's go with "Busted". It was actually  using the vector displace which is (evidently) supposed to be weird. At least it's the same kind of weird in Blender's implementation of Cycles. It makes the displacement all go in one direction instead of along the surface normal. So it does something, but it's definitely not what Poser users are expecting. The vanilla Displacement node is what you're expecting displacement to do.

The Displacement input on the Physical node now has a Displacement node built into it so it should behave more sensibly. If you are working with the Cycles root you should Put a Displacement node inline between the Displacement texture map and the root input.