[quesera]

As a layman, simple explanations for your points spring to mind.

1. An exhaustive understanding of the pyramids and secret chambers would be detrimental to the Egyptian mythos. Egypt owns the pyramids. Western Egyptologists need Egyptian cooperation to learn anything new.

2. Sand-filled wind behaves much like an abrasive liquid. There is more sand in the bottom of a sand-filled wind than in the top.

3. Rotation creates surprising perfection, especially when wielded by skilled artisans. It's rarely the tools that bring results.