This 'Short Cut' preaches about the importance of separating behavior (JS) from styles (CSS) and content (Semantic HTML).
The 'Short Cut' then delves into some actual Ajax code and some examples. (Tabbed navigation, hiding/showing content dynamically, & dynamic select boxes.) It packs a lot in just 57 pages.
The only negative is that the content is slightly 'stale'. The Ajax code and examples may not work 100% in modern browsers. (It uses some feature detection, for example, in determining whether XMLHttpRequest or window.ActiveXObject is available.) It gives passing coverage on JS frameworks and libraries such as jQuery. Much of its content can be found elsewhere, in books and on the Internet.
Bottom Line Yes, I would recommend this to a friend