I'm in a weird halfway space when it comes to touch typing - I can't intentionally touch type, but I sometimes catch myself doing it unintentionally out of muscle memory. There is no significant change in my productivity between when I do or don't touch type, because I'm in the same boat as the gentleman above: I'm spending more time thinking about, designing and navigating code to build a mental map of the changes I need to make and its effects than I am doing the actual code changes, and I often find that means I only need to make those changes once.