Jim,
How close are you to Ft Lauderdale? You may recall that I said that I had Ferrea valves installed in my Z28. Ferrea is loacated in Ft. Lauderdale. Ferrea sells valves for Fiat with triple groove stems. It seems they may have the ability to manufacture valves for the CRD.
http://www.ferrea.com/Fiat-Engine-Valves/p34279 Maybe you could setup an appointment and bring some examples of failed valves to them. If you can bring several broken valves (I would bring the associated keepers and retainers, also), a damaged cylinder head and a damaged piston, it may engage their interest better than just a couple broken valves.
Possibly LOST members who still have broken valves could send them to Geordi to bring to Ferrrea for evaluation? The greater variety of failures seen. the more accurate the analysis.
I hear what you're saying about this being a two day job. I can only speak for myself, but if Ferrea can definitely point to a design defect or manufacturing flaw and manufacture bullet proof replacements, I will go back into the CRD engine, pull the head and replace the valves.
I just had a thought.......This is the first engine that I have heard of the has sacrificial rocker arms. Maybe the hardness of the valves is engineered with the rocker arms to ensure the rockers break before the valves bend. Maybe in some case the valves are a bit too hard and are brittle causing the valves to fail from normal fatigue? I think the new valve design should ignore the part the valves play with the sacrificial rockers. Design the valves for maximum durability. If someone fails to change the timing belt in a timely and the engine is wrecked, then I see that as owner error. It wouldn't be the first time this type of neglect has ruined an engine.