I've worked at a smaller project where it worked just fine. The key I think is to have the project be small enough to be able to fit in my head.
That and have an identical test server. I used to make changes locally, test it locally, then make the same change on test, have someone else look at it, get a lgtm, and do the same thing on the production machine. It sounds like a lot of steps but it is pretty straightforward.
Sadly, it probably doesn't work with bigger teams or more complicated projects.
