I'm afraid I couldn't disagree more with your basic premise:
First of all, you and many other alternative theorists are forgetting one very important factor. To the ancient Egyptians, the king was a god. The living incarnation of Horus on earth. This can be seen not only in the contemporary writings from the Old Kingdom such as the Pyramid Texts, but it can also be discerned from several of the Egyptian titles used to reference the king. Hm.f = His Incarnation; Hr = Horus Falcon; NTR-NFR = The Good God etc... The skilled workmen and conscripted peasant farmers who actually built the pyramid believed they were ruled over by god himself. Since that was their sincerely held conviction, these men would have been more than willing to do whatever their ruler commanded with no questions asked. Never mind the fact that the king was an absolute monarch who held the power of life and death over his subjects. During all periods of political centralization in ancient Egyptian history, but especially during the Old Kingdom, the concept of ma'at (which can be translated as divinely ordained order) was inseparably linked with the will of the pharaoh. For an Egyptian to go against ma'at, by hiding underground as per your example, would have been seen as tantamount to inviting chaos and damnation upon his head.
Secondly, your assertion that the Egyptians of the Old Kingdom would have been incapable of building the Great Pyramid is an entirely baseless assumption. Not only did Egypt have sufficient manpower, an estimated population of 1.6 million of which only about 20,000 men working in three month shifts would have been sufficient, but the copper and wooden implements employed by the Egyptian workmen would have been more than adequate to build the Great Pyramid.
1. It is certainly true that copper, in and of itself is a relatively soft metal. However, Egyptian copper tools and weapons during the Old Kingdom were intentionally hardened by adding arsenic to the mold. This produced a metallic compound that was similar to bronze in strength. Needless to say, the copper saws and chisels would have easily cut through the limestone that made up the vast bulk of the pyramid.
2. For harder stone such as granite, the Egyptians would have used copper bow drills in tandem with quartzite abrasives which would have been more than sufficient to work even the hardest stone known to them.
3. Through trade with the Levantine city-state of Byblos, Egypt received a large supply of cedar wood which was used to construct both the river barges used to transport the granite and tura limestone down the Nile, as well as to build the wooden sleds used to haul the blocks up the network of ramps.
4. Ramps would in fact have been the most efficient method to construct the Great Pyramid. I would encourage you to read the very detailed monograph written by Jean Pierre Houdin. He explains the ancient Egyptian construction techniques far better than I could.
In conclusion, the Egyptians certainly built the Great Pyramid using a combination of manpower, copper tools, wooden sleds, and ramps. And the Great Pyramid was built for and on the orders of King Khufu as his royal tomb. The entire construction project would have been completed in a maximum of 20 years. Recent evidence from the Merer Diary suggests Khufu had a reign of 27 years.