The trouble with that is just because the "backstone" was stood up in the 1800's doesn't mean it was in it's right place, we'd need to know weather the capstone was resting on it for it to really matter, and Roy's already said that the moving could in fact have happened in prehistory, imagine it been built and it quickly falling, would they'd have said "we'll do it again but not in the same way", i believe that stone stood at the back but that doesn't make it for certain the original backstone, I bought his book because i've always thought since i first saw the place 2002 that somethings wrong and out of place and every visit since i've thought the same thing and hopefully Roy's book will give me the answer i've been looking for since 2002.