It isn't really the cruise that is the high risk portion of the flight. It is the bit at the end, especially with any performance 'exposure'. A tilt rotor isn't going to fix those problems.
Also, what about areas such as the SNS, where sectors are often no longer than 40-50 miles? There wouldn't be much point going up to FL250 (or cruising at 350kts) for that.
Tongue was firmly in cheek by the way.
But - maybe the problem is not just the last bit, it is the just the last bit that it finally manifests itself. There are a whole host of other factors that have gone on before that last bit. I for one suspect that some form of fatigue will feature in the final AAIB and any review. It is important that there are many things that contribute to this fatigue. The constant changes from operations, the weather planning and re-planning, performance issues, meal stops, turnaround times, real quality of rest the day before, cockpit environment, commercial pressure to get the job done, the attitude and culture. The list could go on and on. All very real and very underestimated in my view, but also all very fixable without too much effort or cost. 8 hours in a A340 is very different to 8 hours in a EC(Airbus!!!)332L1 or S92. Lucky boy in the 340 has a nice quiet comfy environment, a smiling hostess to bring him coffee and a sandwich. He can wear shortsleeves and can hear Fred next to him without a headset. Fatigued in the 332 yet?
Secondly the sectors in the SNS are small but only if you are flying from the current bases. What if all ops in the UK were able to fly from one or two bases? Most likely a very unworkable idea of course, but don’t dismiss the blue sky thinking either - it might lead to something workable. The flight time would be similar, but cruising at 275kts from one or two hubs instead. A hell of a lot more efficient for all involved in logistics and planning.