I remember when single-page applications were all the rage. I was highly skeptical that they could beat just loading HTML, given that the performance benefits were all predicated upon amortizing the initial load cost over many page requests. It's a very risky bet given that a lot of sites don't have a lot of repeat traffic to begin with, unless you just so happen to be an application in the guise of a website.
Apparently my skepticism has been validated.