Joke all you like, but it would!
No joke Nigel, the wink is for a shared opinion :-)
And why not a Stonehenge-type structure (in wood of course) at the summit of Silbury? It's the one thing that would look right there. The carpentry-like construction techniques used at Stonehenge indicate that such a structure (or structures) once existed so why shouldn't one of them have been on Silbury? In fact it's hard to imagine there not being something of the kind there. And if the height of Silbury has been reduced by a few meters (as it seems to have been) that would have obliterated evidence any Neolithic post holes).
Is there a case for basing speculations on what was there on a sense of what would have looked right? Or is our sense of what looks right completely different to theirs, polluted by having seen Greek architecture?
Now that's an interesting question. I think there is a case for basing speculations on what things would have looked right. You could try applying the idea to things that have survived - would the pyramids at Giza look right with a flat top for example? Or into modern times, would the Eiffel Tower look right with a big round ball on the top - don't think so. So perhaps there's a basic rule of aesthetics at work - it might not be scientific but possibly its just as valid. And when the surrounding landscape is also playing a part in the overall impression (as it does at Silbury) that's perhaps when the 'it looks right' factor really kicks in.
