helicomparitor says:
"its a bit worrying though!"
That's because he is a Eurocopter salesman, and should certainly be worried about 225 sales!
I note the comments he made are quite inaccurate, but are to be expected, of course.
The S-92 transmission has a dual pump system, one shaft lost drive because it wore prematurely. The box had pressure on landing. The crew did as they should.
The spline system used on the 92 is similar to that used on many pumps and generator drives, the plastic prevents spline damage from contaminating the box. There is an excellent team working to identify the cause of the premature wear, of course.
The inputs are not the most critical part of most gearboxes, but they certainly are on the S-61, which has sleeve bearings at very high speed. For the record, only the S-92 and the AB-139 have met the latest FAR/JAR safety requirements in every way, with the certification as proof. Helicomparitor has a difficult time with this fact, n'est-pas?