I know this is the humor thread, but they actually did figure out how the pyramids were built in recent years and it got little media attention. A guy took hi-res photos of the great pyramid and used photo enhancement to mark out the dimensions of each course of blocks. With the heightened contrast, obvious locations of small plinth blocks were shown throughout. They used scaffolds and hoists, then filled in the slots where the booms would have previously been. There are a myriad of primitive levers, pulleys, block-and-tackle, and cranes that could have been used in those slots to lift blocks.
