Yeah wrapping around those prongs seems like the worst thing you can do to that tiny cable. And I don't blame the users for this. I just don't understand why they would put those prongs there.
i.e. Don't pull it tight. I still have power charges from my 2007 MacBook Pro that have not frayed and still look like new and with the adapter from MagSafe 1 to 2 still get used regularly.