He is wrong.
"...I determined that unless you’re a very frequent visitor to one of our sites, you’re visiting us with a cache that is effectively empty downloading many or all of the objects on our homepage. Why? Because we update our pages multiple times per day."
Totally wrong. His front page is 11.7K html and 278K all other things (css, js, img etc, based on YSlow data). His site's burden to a visitor with a primed cache is 22K. Even if he updates all the content in a single day, his non-primed data will be 22K and that's all.
His site does not employ far-future expiration day strategy. Steve Souders explains them all, every web hacker should read his books.
