LOL, JoelM hilarious.
As for going blind while doing the "regular" (man, JoelM now that association won`t get out of my head
) iron palm, I think it`s possible, but not likely.
I remember reading something from Jang Jwing Ming about doing pushups on the fingers. He said something about not doing them on fingertips, because it can effect (injure) the nerves there, and have a bad effect on the organs.
I think Mikhail Ryabko said that doing too many straight punches can make you go blind too.
So, I believe it`s possible...