Not that MPP said much about it, but I find that a bit of a murky area.
I wanted to ask him about stuff like the avenues at Avebury, which came later than the circle, iirc, well after 2400bc. And the barrows that surround Avebury, what does that indicate in those terms?
The RSCs are another example where there seems to be a blending of ideas rather than some kind of 'take over'.