Nice post: author has good communication / teaching style, and firm grasp of the material. The visuals help make some of the concepts more intuitive. Bookmarked.
On an unrelated tangent, the way the page formats when printing is one of the best I've seen. No weird navigation cruft, and it seems there's even a style defined that sets book-style margins, such that the left and right margins alternate in length.
Thanks! This particular article went through pretty extensive feedback with colleagues where I'd print the article out, share it, and get hand written feedback. This necessitated investing in print formatting. :)