Re: Good failure analysis starts *long* before the rocket launches.
While you may wish that was the case, reality is far different. You design for failure modes; you verify critical cases, do verification fm with instrumentation in qual and flight test; and eliminate as much instrumentation as possible for weight and cost. The closest you come to your imagination, is a top level failure modes and effects analysis, with a ranking items that cause loss of the vehicle or life (ground or on orbit if they get that far.). There is hardly a detailed fault tree. At the top they have some bright people to connect times and observations but this is too quick and too simple to reflect a detailed fault tree analysis.
And the designer of the strut could only design to the load cases supplied by Space X. Space X is responsible for doing a design review. I don't understand why so many fanboys believe all the PR and give Space X a pass on their responsibilities? Space flight is tough and when you cut corners and reviews this is what happens. Maybe this was a new lesson learned or maybe the bright new engineers missed some basics from past lessons learned.