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Neither can ZBrush or any other modeller.

Wrong.

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Not on a "life" Poser figure, because Poser will break up the figure into sub-objects when it loads it from the figure library.

The geometry of a Poser figure (OBJ file) is made out of several parts (this is the standard way to do it - not only in Poser). Other modellers like my Cinema4D are able to work with several groups at once. These combined groups are seen as "pixel clouds" and I'm able to manipulate them precisely with all the many tools C4D has (this includes something similar to Posers morph brush, but more accurate and mutch faster). Other professional modellers are able to do the same.

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I made several full body morphs with the morphbrush this way, and I can't think of a single time I rather would have used ZBrush instead, because it's so much more convenient to work directly in Poser with a fully articulated "life" mesh.

Morphs made this way most often comes out with distorted geometries. Mixing those morphs with others (original DAZ morphs for example) will often result in a desaster. It is allmost not possible to manipulate a single or at least only a few points from a geometry. Exact control of how points are moved when you move the mouse is not possible at all. So results are unpredictable.

Poser seems to "jeopardize" with the  normals while using the brush. Raytraced renders may come out with darkened or completly black areas.

Posers morphbrush is very nice if you feel a need to give your character a big, long nose. Or to do other things like that. And I'm very happy to have this tool to correct things a bit (cloth with stick throughs where hiding the underlaying bodypart isn't possible, for example). And yes, it is a wonderfull tool for beginners. But that isn't what was asked for in this thread.

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