As an aside, it seems to me the anti human transport rhetoric is frequently based on saying it would be a feat so great that it can't be credited (I think Brian Mountainman said as much when he came to TMA). Yet measured as distance x weight the sarsens were a bigger deal and no-one says that was impossible.

In fact, the bluestones were a much smaller deal - they were sufficiently small at 3 to 6 tons they needn't have been dragged, they could have been carried.