I've never had any Apple cord separated.
One time though when I was playing football on the street my iPod Touch feel out of my pocket with the headphones connected and right next to it.
I realized about 2 hours later and ran back to find that the whole thing was run over.
My iPod was fine (screen in tact, everything 100% the same except for scratches on the edges), however the headphones were busted up extremely bad.
I went to the local Apple store and told them the story exactly as it happened.
NO receipt, NO proof. Just had to show them the iPod and they gave me a brand new pair on the spot free. I was in the store for LESS THAN A MINUTE.
I've NEVER had problems with a cable of theirs breaking before. BUT EVEN IF I DID, and EVEN if it was a once a month occurrence, I wouldn't give a DAMN if they just replaced it like that every time!