Not only am I deaf and dumb, here in Germany, but I'm also functionally illiterate.
That's truly an eye-opening experience, and relates a lot to the work I did this summer.
In one sense, a native English speaker in America is a little better off than I am – he can at least ask questions if he can't otherwise glean the information he needs. That's difficult for me.
(However, the other day I did manage to ask someone in the grocery store the other day which of the butters contained salt. German uses so many compound words that even though I might have recognized "saltz" in the word, for all I would know it could be in a word saying "no salt." But then today I tried, and failed, to buy facial soap since I couldn't be sure what it was what the clerk suggested I buy really belonged on my face... Sometimes I get lucky and the packaging includes alternative versions in French – and I tend to reward those products with my purchase – but it's fairly rare and only slightly more common than packaging in English.)
But it's still very debilitating, being locked out of visual language. I think literate people may not even realize how hard it is, since normally we interact with writing so seamlessly, so automatically. Consequently it can be hard for literate people to realize just how writing-dependant modern life is. For those who can't though, their faces are pressed up against the glass of a world they can see but not enter.
This summer when I wrote my housing self-help documentation I did it with the intention that it be understandable to people with low literacy levels. It was hard to write that way, though, since the law that I was explaining was very precise and required precise language to explain. Such language is hard to make understandable to someone whose reading skills are at an elementary school level.
Had I had this experience first, though, I wonder if I would have done it differently, or at least done so with less hypothetical empathy and more actual empathy. In that I've now been there too, being locked out of the words I need to know, and know first hand it's not an easy place to be.