Interesting comments about the adequacy or otherwise of the design and engineering etc.
The cause of the damage to the gear and why it failed seems to be possibly strongly
connected to the fact that the gearbox fell off a truck in Australia.
That seems to be the angle the AIBN in Norway is taking from their last report.
As has been previously stated the other issue would be that damage of any kind
cannot be adequately determined in advance in service due to various failings
under the existing criteria.
Whichever way you look at it it is a huge clusterfu@k that will take a lot to rectify.
It will be interesting to see if the type survives of course in its intended role.