Though this looks to be a case of a defective friction disc, clutches are not normally covered under the power-train warranty. They're listed as a wear item, much like brake pads.
Nonsense - even if it adds 1 hp, it gives a clear reason to deny warranty. Amount is completely irrelevant. If you're moding the vehicle, be prepared for potential consequences. Simple as that.
But that's the American way damn it! Haha but this is truth, if you come at me like this at work you can go kick rocks. I have went to bat for many customers for goodwill repairs for situations like this. Best thing you can do is be calm and understanding. Explain that though the car is modded it is not driven in a manner the explains the failure. And you're willing to be patient and go through the necessary channels to get the component covered by Ford. Or at least hear from the Ford field rep that there is no way the clutch was defective. And it was your fault. With an explanation on how he came to that determination. Which I don't think they will be able to do by the way it looks. Chances are he may not even go there and just tell them to replace it.
^^^ This. Sorry, OP, but the mods to your car have absolutely nothing to do with this, it is simply a wear item that is NOT covered by the manufacturer's warranty.
Thanks for the thread synopsis but maybe people want to continue to have a back and forth about it?