Note that the author of the article doesn't advocate forgoing local commits, but something like Facebook's work on a semi-distributed Mercurial, which allows local commits without cloning the entire history to each client. Here's the relevant section from the linked post[1]:
But what if the central Mercurial server goes down? A big benefit of distributed source control is the ability to work without interacting with the server. The remotefilelog extension intelligently caches the file revisions needed for your local commits so you can checkout, rebase, and commit to any of your existing bookmarks without needing to access the server. Since we still download all of the commit metadata, operations that don't require file contents (such as log) are completely local as well.
But what if the central Mercurial server goes down? A big benefit of distributed source control is the ability to work without interacting with the server. The remotefilelog extension intelligently caches the file revisions needed for your local commits so you can checkout, rebase, and commit to any of your existing bookmarks without needing to access the server. Since we still download all of the commit metadata, operations that don't require file contents (such as log) are completely local as well.
[1] https://code.facebook.com/posts/218678814984400/scaling-merc...