White Silbury is getting dismissed too readily I reckon. Do we know, for sure, there was never a time when it wasn't white? Or that white was never part of an intention, at any time? One thing we do know - they kept changing their minds.

Is an intention to scour so unthinkable? (Wot about the White Horses then?). Do we know how labour intensive it is, and whether if they did it for a short while there would be identifiable marks? Maybe they tried it for a few months, found it hard and said sod this we'll change the plan, let's cover it? (Are the dampers on the Millenium Bridge part of the builders' ritual intention?)

So is there a case for saying we should recapture their Oh-so-short-lived original intention for them? (I'm not really advocating skinning it, but there's only one thing we know with reasonable certainty about what they intended - to make people go Wow! Making it white might not recapture the physical reality but it wouldn't half recreate the emotional one.)