Nothing advanced about that at all.
Yeah that's so retarded nobody have any clue how they did it and nobody managed to do it neither in later on civilization. Good job Mr. Dissmissal.
Many proposed methods, but we dont know which they used. It doesmt really matter.
Such as? Which tool exactly that doesn't leave any marks?
Most of them when used properly. Not to mention whatever Mark's are easily weathered away.
A lot of blocks haven't suffered weathering because they was burried.
This is utterly false. No cuitting tool on earth doesn't leave any marks.
If we are just talking easily visible Mark's then you are wrong. I do it all the time.
No, we are talking microscopically.