I don't know why casa bothers about TBO's . When you think about it every engine flies 'on condition'. If a 1800 hr TBO engine chucks a con rod through the block at 50 hrs you don't just carry on for another 1,750 hrs because casa said it should be good for that time.
It all comes down to the mode of failure in high time engines. If impending failure gives plenty of warning then why not run them till you get tired of topping up the oil.
It appears that catastrophic failure is much more likely to occur early in an engine's life or as a result of maintenance errors than it is due to high time.
Even underutilized engines generally do not fail catastrophically. They simply wear out quicker than frequently used engines.
If casa wants to do something to help GA it would be better employed tuning up the suppliers of aviation parts and supplies. In my association with aviation I have survived the biggest fuel contamination scandal to occur anywhere in the world, TCM cylinders belling out the tops of their cylinders, Lycoming killing people with dodgy crankshafts, TCM neglecting to do adequate quality control resulting in a rash of improperly case hardened followers and thus ruined cam shafts. Now we have TCM selling new cylinders which don't seal properly brand new from the factory causing more expense as Aust engine rebuilders have to check all of them and reseat many. These are just problems that have affected me . There are plenty more.
All of the above list has cost operators collectively millions and what happened to the perpetrators ? nothing ? a slap on the face with a 3 day old lettuce leaf ? Not much that's for sure because every couple of years they manage to inflict some new expensive,dangerous blight on our industry.
Oversight of these companies by casa with half the enthusiasm they they have for trashing perfectly good engines would bring about a safer, more affordable and happier GA community.