Not to argue just to argue, but I think that illustration you gave is the reason shops don't warranty engines for the most part. Detonation is NOT the pistons fault, and the owner got what they deserved. More than likely someone at that company was recommending hyper. pistons to everyone and then realized they were wrong.
AFAIK almost ALL new engines from all major manufacturers use hypereutectics (except I'm sure in things like diesels) because hypereutectics are lighter and expand less. A few less grams reduces reciprocating weight by hundreds of pounds, and thus, you get longer engine life, and more power. (ability to run tighter clearances and less mass to turn) None of these are bad things, and if most powertrains are coming with at least a 30,000 mile warranty, the manufacturers must be fairly confident in them.
If they were that bad, no one would use them, and thats not the case. If they were so horrid, there would be lawsuits right and left, and there are not. They are not right for every application, nor are cast, nor are forged. In any case, I can't find it now, but I was going to show that TRW has a chart somewhere online showing that forged pistons are the ideal material for every truck engine, (light truck) and IMHO, that is simply not true, and never will be. But yet thats a *manufacturer* stating this. And thats what I'm sure happens with most failures of hypereutectics...being used when they shouldn't be, probably recommended to people that should be using something different.
You have a point about the "brittleness" of the alloy, and that is correct. Hyper. pistons are NOT forgiving. but if you don't do stupid things with them, stupid things won't happen. I had a motor with a hole in a cast piston...that doesn't mean that cast pistons suck in all cases.
So just because someone blew up a hypereutectic piston doesn't mean they are all bad. Cast pistons are destroyed all the time too, by idiots using huge shots of nitrous on them, or revving the heck out of them, boosting them, whatever. Hyper. pistons were not designed for that type of abuse, and an improperly operating engine (detonating) is no excuse for some company or individual to claim they are faulty.
Now, when (and if) I ever get my motor pieces back from the engine shop and get it assembled, I will be right back on here the day that one of the hypereutectic pistons comes apart. It will be 9.5:1, and I have *no* qualms about running them whatsoever. I just know that I probably shouldn't expect to turbo the motor and run 15lbs of boost, nor rev it to 8000RPM's every day.