[geuis]

There's a second video that addresses this that's linked elsewhere in the comments. Basically he outlines some evidence for a high pressure natural spring underneath the pyramid, and that some of the branches off the main burial chambers that have never been adequately explained were used to fascilitate water movement. For the last few levels, he proposes a regular old bucket line. Over all, not implausible. In some ways, more so than the standard heave-ho theory.

[Someone]

A natural spring in the desert that fountains water up 100+ meters, and they decide to put a huge pyramid-shaped stop on it, presumably to get rid of the luscious oasis that must have been there? And that fountain somehow, in thousands of years, didn't find a new way out through the limestone, which is water soluble?

I think it is more likely to claim there was an oil well there.

Edit: it wasn't a desert at the time they built the pyramids, but blocking a natural spring never was a good idea over there.

[Geee]

The spring theory is really the only theory that answers the 'why' part of the equation. I mean, in the presence of a high pressure spring, it would be natural for people to kind of just stumble upon a building technique like this. People would first make a pool by laying rocks to form walls, then they will start making the walls higher, then realize that they can use buoyancy to lift heavier rocks. Then engineer comes along and realizes that they can make a huge building, and thinks: 'why not?'