That is one heck of a pour to last thousands of years. The exterior forms would be ridiculously complicated as well. The exterior shows individual blocks.
It appears as if ancient Egyptions as well as whoever built Puma Punku may have had technologies for working with stone which would have been beyond what we have. They actually had vases made of diurite, which is not much different from making a vase out of solid diamond.
I read about the quarries upstream of the pyramid sites where unfinished stones are still insitu. I think that they used ropes pulled thru the cut with grit on the rope to do the cutting.
I believe he is saying each individual block was poured.regards!!