Oh my, you have really brought all of the fringe assumptions to bear all in a single post! Where to begin...
Well, to start off and in response to your earlier post, I believe and with all due respect, that trained Egyptologists such as James Allen (who are experts in the Egyptian language) are more qualified than an untrained though intelligent layman such as yourself. If they have concluded that the word "tA-rd" means "ramp" than only another Egyptologist with linguistic training could justifiably take them to task.
Regarding your assertions about the later pyramids: You are correct in stating they are of an inferior design than the Fourth Dynasty monuments. However, this was the result of political and economic factors, rather than any loss of architectural knowledge. The construction of the giant pyramids of the Fourth Dynasty, which totaled six such monuments, almost certainly took its toll on the royal treasury. Consider similar projects in this day and age. Remember the proposed "Bridge to Nowhere" that was proposed by the United States Congress? That was shot down almost immediately due to budget constraints. The Egyptian kings were under no such constraints, and had no limitations on their personal authority. Be that as it may, there is some evidence (which includes the sudden shifting of the royal necropolis from Giza back to Saqqara, as well as later literary evidence from the Westcar Papyrus) that the advent Fifth Dynasty may have been nothing less than a change of regime. Indeed, historian Susan Bauer has proposed the rather convincing hypothesis that the Fourth Dynasty fell due the tyranny of its kings. If we look back to the origins of the Fourth Dynasty, we can see that the first king of this line, Sneferu, seized what little regional autonomy remained among the provincial aristocracy. He did this by replacing the local administrators, who were previously selected by the king from among the provincial noblemen, with his own hand picked court officials. Most of whom were related to the royal house. This process continued throughout the Fourth Dynasty.
Sensing political unrest amongst certain segments of the Egyptian elite, the priesthood of Re, which had been subordinated to the king beginning with Sneferu by appointing a royal son as high priest, perhaps initiated a coup de'tat with the support of a lateral branch of the royal house. This most likely gave rise to the Fifth Dynasty. Read Mark Lehner's "The Complete Pyramids" and Susan Bauer's work on Ancient History (the title of which unfortunately eludes me), for further details.
The new ruling dynasty, with a significantly weakened treasury combined with a new royal mandate placing increased emphasis on the solar cult of Re, would have been obligated to build a much reduced pyramid tomb. Compare the inferior superstructures of the pyramids of the Fifth and Sixth Dynasties with the eloquently made adjacent solar temples, and you will get some idea of this.
As for your assertion that there is no evidence for any pyramid having been a royal tomb, I believe I have negated your objection to the evolution of mortuary architecture. There is also the presence of the Pyramid Texts themselves placed inside the burial chambers of pyramids which were clearly written to assist the deceased king into ascending to the afterlife. Mummies have also been discovered in several pyramids including the Red Pyramid, G3, Unas etc...
There is also the presence of an obvious stone sarcophagus inside the Great Pyramid which I have yet to see any fringe theorist address with any degree of adequacy.