This has been available in the Google Web Toolkit since 2006. I'm not sure why a Google employee would not have been aware of it. If you use GWT, only the bare

This has been available in the Google Web Toolkit since 2006. I'm not sure why a Google employee would not have been aware of it. If you use GWT, only the bare minimum of resources (JS) are loaded to render the landing page. Further JS will be loaded for subsequent pages/actions as needed. Images and CSS are inlined too so that there are no requests for them. "Perfect caching" of resources is built in through MD5 names for resources so that with a simple apache filter you never download static content twice. I'm glad to Feather worked so well. It always drives me nuts when some major site/portal needs 250+ requests to load. If you like the sound of it (only 3 requests to load a complex app), checkout GWT as you get all of these optimizations (i.e. Closure) and more by just compiling your web app.