Yup - that's certainly removed the white bits I was seeing... which were mostly coming round the edges of the fingers.

For realism, you, of course don't probably want it too smooth... I'd reckon.

But it depends - the latest version with no bump now looks like the girl has a much better hand moisturising regime ;)

I wonder if the remaining white blips... which to be honest I'm struggling to make out... are derived from the Turbulence node on the Alt Specular channel... or if they are a scatter artifact... or just good old raytrace / mesh bug related fireflies?