I should have added no suggestion of intentionality .
Phew, that lets off my tool shed and almost every house built by Barratts.
(And the scarp slope of most of the Cotswolds).
Your tool and any house would have a very short roll , not worthy of the term and not seen from an associated prehistoric site . Likewise the Cotswolds scarp slope but more importantly they were not man made .
The point I was thinking about regarding the Cotswold scarp was that Silbury's slope is at its natural slope of repose - which adds a whole other uncertainty into claims it was "meant".