Neither cracks nor the repair to that A300's empennage had anything to do with the separation, which happened considerably beyond the Ultimate Design Load of the vertical stabiliser.
Indeed .. These cracks are not (according to the report) a contributory factor
However the NTSB revealed by examination of other aircraft in the same series .. cracks that existed and had not been detected by maintenance services .. as their means of investigation were not suitable
It is clear that this finding by the NTSB and the development of new means of investigation has certainly allowed to prevent accidents from occurring in the future
This extremely wrong and dangerous "method" has been used by the copilot on the flight AA587 in the wake turbulence over the Queens : THE RUDDER BROKE (Nov 12. 2001).
Methink that the point of "roulishollandais" was about "wrong method" and this can be dangerous .. as it was show by the A300 case (obviously the pilot used the rudder control in a way that it has exceeded the certification of resistance of the materials concerned .. but if he had not used this method .. the accident would not have happen)
Unlike AA587, the AF447 vertical stabiliser had a large chunk of fuselage attached to it
Indeed .. again ...
Nevertheless this does not prove that the vertical stabilizer separated from the plane in contact with water or when it was in flight
Other elements of the survey suggest a near certainty that the vertical stabilizer separated from the fuselage on impact