Cached or uncached is not relevant to the article. They are talking about using nginx as a load balancer. It just proxies all requests off to the application s

Cached or uncached is not relevant to the article. They are talking about using nginx as a load balancer. It just proxies all requests off to the application servers that actually prepare the results. This article is really just about the fact that nginx can efficiently service a very impressive number of connections at once. Those backend servers will be using caches of course though.