A slideshow, in chronological order, showing Khan's growth as an architect and his concentration on the relationship between people and the buildings they live/work in.
I agree - this is what a sketchbook should look like. He's building a catalog - a library of images, ideas. There's a hand, there's a foot - it's all there without a lot of editing. So - he's just allowing these things to happen. He's allowing this growth to occur probably before he can label it this or that.
By the way - judging from the color of the paper and the rounded corners - he is undoubtedly drawing in a Moleskine®
Artist's blog that I've been watching for a little over a year now. His digital stuff blew me away initially, but I prefer his pencilwork now, after seeing pages of his sketchbook