That kind of text will still confuse the majority of Web users. It's the kind of thing my mom or wife would show to me and say, "So am I supposed to put my state in? Why do they have it there if I'm not supposed to fill it in?"
roel_v makes a valid point - the majority of web users will not see this text. The whole point is that it's hidden and will only be 'seen' by people using screen readers. The text could easily be changed to "To reduce spam we have included this extra field. If you are a human, please leave it blank."
It was a valid question - the GP was talking about blind users, and then some guy who didn't even read the discussion properly comes waltzing in with a non sequitur about his mom.
