[keithblan]

I've had this problem and I think the answer lies in the use of Texture controls.

In "Help" it says:-
----------------------------------------------------------------------------------------------------------------------------------------------------------------
This controls how much skin texture to apply in areas where skin texture is being corrected. This texture goes into touch-up brush strokes and areas where the sliders have had an effect. You will need to zoom in the picture to see the effect of changes to the skin texture. Pressing the Texture button opens the following sub-sliders:

Brightness
Finer control over skin texture brightness.

Saturation
Finer control over skin texture saturation.

Size
Makes the synthetic skin texture pattern larger or smaller.
----------------------------------------------------------------------------------------------------------------------------------------------------------------
Not sure how PP decides where to apply skin texture correction but use of texture controls does only seem to affect areas where "roughness" has been created, at least in the images I've tried.

Hope this helps.