Can you say for sure that a good suite of functional tests wouldn't have saved your bacon as well? And they might have been much easier to write and also catch

Can you say for sure that a good suite of functional tests wouldn't have saved your bacon as well? And they might have been much easier to write and also catch a whole lot broader set of problems at the same time. The post isn't advocating having NO tests. It's not even saying that unit tests don't work. Just that they're not necessarily the best value in every situation.