Are their yields actually that good, then? Are some of these chips massively underclocked? Do they add extra cores and cache for redundancy? Or maybe they have

Are their yields actually that good, then? Are some of these chips massively underclocked? Do they add extra cores and cache for redundancy? Or maybe they have no idea, and TSMC delivers only chips that pass QA. For as big as Apple is, TSMC is in the stronger negotiating position.