In reply to Chuck.

You seem to be conflating many different issues.

Using JS to dynamically load content directly instead of forcing complete page reloads has nothing to do with MVC, OOP or PHP.

Individual users may not complain about performance, but how they use a site can be analysed statistically, and it's quite clear that fast page loads are beneficial. It's also quite clear that pulling in some JSON is less resource intensive on both the server and clients bandwidth than forcing entire page reloads.

Whether this is worth the effort for something as basic as a blog, is another question entirely. But it doesn't nullify the benefits obtained in doing things this way.