Hiya. Actually there was an engine change due Spline wear, but the Brass at RR call it an oil fire, not specifically Spline Smoothies. #2. QF32.
Given what's known, and your perspective, it is at least a good guess that RR have mitigated the cause of Spline damage by acceding to Inspections, as to my way of thinking, they are eating canal mud on LAX SYD.
No, not really. They have mitigated the focus on the actual problem by eating a swap/strip/rebuild at an agreed interval. This interval is Qantas' schedule, and EASA/ATSB mandates, with input by RR. Most expensive, but the alternative is a re-design to eliminate Resonance discovered in 972 test, but ignored because it was a "family tradition" to mimic previous test and banked approvals via certificates in the dusty files.
Who throws in the towel first?? I think RR will keep eating. They cannot retool and recertify, and "Continued Airworthiness" via a Permanent AD is too, what, Public??
There is precedent for engine swaps, Bolty, dozens of them. The Firm dog chewed a relaxed inspection interval by convincing EASA that the Splines would be "just as well" investigated with "averaged" crest wear at abutments instead of a mandated strip search at "worst case wear" involving but one Spline per Coupling set. This is in the Public AD divulgences, and speaks volumes.
Oil is hot because the engine is light, floppy, and viscous deficient with time in case of approved oils. The FOHE also does a crap job of cooling the oil when Fuel is Warm, just after launch, just as it does a crap job of heating Fuel when the engine is cold soaked, and the Oil is cold soaked, (At Altitude, or long CDA) or missing, due bypass to Air cooled Route in the Oil Path. It's all in there, and the Splines are complicit, but only as the canaries, just as the Bearings, Oil Tubes, and Oil system are likewise.