Ok, that is an amazing theory, and regardless of what happened in the book(s), that just became my movie-verse headcanon -- mostly because it *does* rather make sense of his incredible Other-ness (even for being an Elf, Thranduil is very Other and distanced from reality) and of the admittedly odd way he moves. And just because it's amazing to think of the story possibilities.
I... I didn't want to believe it, but the more you think about it, the more it makes sense. After all Celeborn doesn't behave that way, through is is himself both Sindarine and of royalty so I can't find any other reason for his strange behavior movie-verse...
Not only am I a bit tired of how every characters viewed as jerks end up hiding huge secrets making them secret victims in fan-works, but also, as a Moriquendi fan, I don't think that the Elvenking Thranduil will ever need that kind of background cheat to explain his actions, since thoses already made sense as far as I was concerned. ...Book-verse at least.
Darn. Now the weight of this Blind King theory is getting obvious and obviouser by the minute. X/
PS (to Aiffe) : You're a somewhat-annoying-definetly-amazing-clever-headcanon-breaker of a fan, you!
Holy crap. The next based on that pic is just.. wow. I never thought it that way, but I noticed that Thranduil acts wery strange. If he is really blind, a lot of things would make sense. But what would happen with him in the last movie when he is supposed to go into battle? I can't wait to know!
Maybe he can will his eyes into healing just enough for a limited span of time when he has enough energy...and just use his hearing or something a form of elvish thelepathy (osanwë-quenta?) to fight during battles.