What if the actual process was that the ancients had a way to heat up the stones in a very targeted way at the molecular level, but not necessarily with fire, and not to melt the stones fully, but to instead get them close to an almost lava-like state, with the stones interior still being solid, but sections of the exterior surfaces reaching an almost lava-like state, resembling hot coffee taffy. Here, the blocks already in the wall would be closer to normal temperatures, as they begin to cool. But the blocks currently being lifted would be closest to this gooey lava-like state, such that once placed atop the other blocks that would adhere to the other blocks' shapes and contours. Also, perhaps rather than using straps, ropes and chains, which would get in the way, since ropes and chains would have to go beneath the blocks, what if they used clamps that look like ice tongs, which they set to fit beneath the protruding knobs seen at the sides of all ancient blocks?