As someone who has worked on very large networks for 15 years, the author left out some important bits about using caching with thundering herd problems.

You really need to make sure that your cache settings will not generate a ton of requests to the origin when new content is requested.

If you have a bunch of clients that are going to request content at nearly the exact same time (this happens a lot with live video streaming, but can also happen when your clients are configured to download something as soon as it becomes available, or on a schedule, etc), you need to make sure your caches are set up so that the second request will wait for the first request to fill from origin rather than send its own cache fill request. Ideally, if 1000 clients all request the same content from your cache, only ONE request should go back to the origin, and the other 999 should wait and used the content retrieved by the first request. Otherwise, your cache isn't going to do anything since every request is going to require pulling from origin anyway.

In nginx, you do this with something like the proxy_cache_lock setting.