Everything about the TRENT's shortcomings suggest a vibration environment that was not designed for. Not particularly alarming. However, there are identifiable structures within the Modules that give evidence of an inability to withstand something that should by all reason be a slam dunk. Early Bearing failure, followed by unusual and surprising wear signatures at the single most important structure in the Powerplant, the Joints of the two articulating Shafts. These Splines are not life limiting, ordinarily, as other patent foibles will cause an offwing strip well ahead of any weakness in the Coupling. Just after the Burst, RR stated the failure was in the Rigid Coupling, and even though additional findings have been introduced since, they have not backtracked. Likewise, cancellation of post burst emergency ADs is to be expected; "better safe than sorry".
What is left is the fourteen month journey of the very problem that by Rolls' statements caused the burst. Oil Fire, Overspeed, Transient Ductility in non ductile material, etc. etc. Hot Oil, Oil Tube fracture, and on, and on.
Rolls have accomplished what needed to be accomplished, and without a Regulatory grounding of the Type. This had the added benefit of keeping the "C" MOD Proprietary, and away from Public scrutiny. The Inspections of the "C" Mod are known, however, and how they relieve the manufacturer of disclosure and a further exercise of responsibility is the key to current philosophy relative to the Fox guarding the Chickens. Thus far, just a few feathers, nary a drop of Chicken Blood.