This is addressed in the article. > So, we decide to make our server's life easier by trying to ensure, from the client, that it doesn't ever have to handle mo

This is addressed in the article. > So, we decide to make our server's life easier by trying to ensure, from the client, that it doesn't ever have to handle more than one request at once (at least from the same client, so we can assume this is a single-server per-client type of architecture).