So true. I really hope that doesn't happen, even if the possibility of it occurring is slim.I'm still holding to the belief that Zoro is keeping his eye closed for the same reasons some pirates wore eye patches back in the day. So they could keep that eye adapted to the dark. Other than that I can't really see a reason why he would keep his eye closed (Unless he's lost it)
Revealing some weird eye or something would be incredibly stupid IMO.