Interesting theory methinks, but if you're like me, the article and tiny little photos left me going "whaaaah?" To see the full 3D demonstration which explains things
much much better, go here:
http://www.3ds.com/khufu . But first you'll need to install the plugin located here:
http://player.virtools.com/ (if you're using Firefox, they don't make finding that link particularly clear). The 3D demonstration is like a History Channel video game, the idea of which, fully fleshed out, doesn't sound half bad.
By the way, I give it a graphics rating of 8.0, a story rating of 9.0, and a control rating of 2.5.
A problem I have with the theory is that they don't explain how the inner ramp is disassembled and/or filled in. Also, they don't present any evidence that the inner ramp's archway of sorts is actually still physically there inside the pyramid. Looking at the 3D presentation, it looks like the archways would be fairly easy to find, and I think would have been found a long time ago if they were indeed there.