Did you actually play with the url? It pulls in the dependencies in one file, in any order. The genius part is that it's creating cached custom dependencies for each page that could potentially be shared by other pages. This is the most efficient dependency management approach I've seen. For sites that could have hundreds to thousands of pages, css/js asset & dependency management is so critical.
Something doesn't need to be difficult to implement to be extremely useful.
If you like that idea, you might want to take a look at library I am developing in my free time.
The idea is that you specify things you need (for example Mootools:Core and Mootools:More:FormValidation) and dependency manager pulls the required code with dependencies in correct order. It is in ruby, though (rack middleware + standalone packager).