Although the article has an SEO-optimized vibe, I think it's reasonable to take it as true until refuted. My rule of thumb is that any rarely executed, very tricky operation (e.g. database writer fail over) is likely to not work because there are too many variables in play and way too few opportunities to find and fix bugs. So the overall story sounds very plausible to me. It has a feel of: it doesn't work under continuous heavy write load, in combination with some set of hardware performance parameters that plays badly with some arbitrary time out. Note that the system didn't actually fail. It just didn't process the fail over operation. It reverted to the original configuration and afaics preserved data.