they could change something about the knock sensor or coolant or some other thing to avoid damage specifically to that piston. It just doesn't make sense that its only mildly modified cars and only that piston with this issue(even tune only), not the supercharged or n2o cars, not any other problem that you'd think would pop up with a bad tune. With the 3v you would see certain pistons(or rather control arms) fail with too much boost/bad tune so usually you'd see 3 or 6 blow or whatever, i can't remember 6 or 7 maybe.. in any case, it wasn't always one weak point, it was just pushing the stock internals too hard.
What about the tune is causing this specifically to happen to that one piston in a handful of engines when most peoplare fine pushing much more power or with the same tune? The burden of proof is on Ford. just because we haven't seen any posts from people with #8 issues while stock doesn't mean there aren't any or wont be any, this car has only been out a little over a year. what if it's just that #8 is getting too hot in some vehicles?