Just to agree with the other's reply here: I am not blind, but do touch typing. Sometimes I don't even look at the screen or keyboard since I've learned to copy

Just to agree with the other's reply here: I am not blind, but do touch typing. Sometimes I don't even look at the screen or keyboard since I've learned to copy things (Such as a paper I've written by hand). You do get to a point where you develop a "sense of typo" and can simply correct the mistake. It has its limitations: It doesn't help you spell better, only correct typing mistakes.