What he's doing is "staggering" the height of bowl rims, since they're all the same general height - so he can place them closer together and fit more per shelf - very smart way to load. People who are good at Tetris and puzzles excel at kiln loading!
The other method you got confused with actually used to be common in ceramics. Example: saggar fired ceramics used to be common when you had "dirty fuel" sources to fire your kiln. Inside these saggars it was common to stack/cradle glazed bowls inside one another, to maximize your volume. Since glaze obviously sticks to anything it touches, they would space the bowls apart with 3 small balls of wadding/clay to separate them - the balls would be under the clean foot ring of the top piece and they would clean a circle of glaze where it touched the inside of the bowl underneath - this way nothing sticks to glaze, its all clay-on-clay. So if you see old Chinese ceramic bowls with 3 unglazed dots in the center, it was likely fired this way and very old.