An interesting back-story, similar to my own. As I mentioned earlier, my eye-patch was a reward from a quest chain in the Blade’s Edge Mountains of Outland.
At the end of this chain, I do battle with a gigantic gronn named Goc (one of the famed Sons of Gruul). This is done at the behest of Baron Sablemane…who is in reality, the black dragon Sabellian (one of the sons of Deathwing). Even though I succeed in slaying the gronn, my story is that I loose the use of one eye during the fight.
In gratitude for eliminating his enemy, Sabellian enchants the eye-patch to not only restore my vision, but enhance it in various ways. This is why…no matter what xmog outfit I wear…I always keep the patch.