A northern thing? Not entirely.

Pete, you're the exception to prove the rule :)

When it comes to hardness of stones, owt would seem soft if you're used to sarsen. I think the texture is key to definite evidence of humans faffing about making cupmarks. Those Fyfield cups do look more ground than pecked. I reckon if the folk back then knew that the local stone could be worn smooth (e.g. the polishers), they might have modified pre-existing natural cups at Fyfield by smoothing them. Other than the pollishing stones, I can't think of anything at WKLB that's as smooth as the cups on Fyfield.

Pete, I'm having a few doubts about the grooves at WKLB being used for sharpening. When you showed us the Polisher I think that we were all surprised at the glass-like smothness of the surface. I remember our discussions as to whether a grinding paste must have been used, for example, try to get an edge on a chisel on a sheet of glass without any.
Comparing the marks at WKLB http://www.themodernantiquarian.com/post/20276 the surfaces are still rough, how is this possible?