Pyramids - Block moving & Bevelled sides

I have read a great deal on the subject of Pyramid Building (being retired now and having a back problem that limits my sitting up and reading these boards to a few minutes at a time) and thought you might be interested in this site www.world-mysteries.com... by Gordon Pipes who has proven how easy it would have been to shift these blocks using his lever system and has a video showing how. The numerous theories regarding this subject all work way outside the 20-30 year time factor except this one. Using small gangs of volunteer labourers working from all sides of the structure (the number of gangs being reduced as the structure got higher) I believe it would indeed be possible to complete the Pyramid withing the 20-30 year parameters using this method.
Last year I saw views of the Pyramid that showed that each side is bevelled inward slightly down the centre of each face which could be clearly seen as the suns rays crossed the face at certain times. It was again yet another mystery of these wondrous structures and added yet another question to the centuries old 'how, who and why' debate.
Since seeing these 'bevels' I have not come across any explanations, suggestions or further discussions and wondered if anyone else on these boards could enlighten me.
Have a nice day everyone.