[loup-vaillant]

This is not about typing faster. This is about lightening cognitive load. For instance, I don't use my vision to type. Rather, I think "stretch my right ring finger to get the [O]" (except I don't actually verbalize it, it became automatic now).

That mean my vision is free to concentrate at the screen. That means that my short-term memory don't have to memorize what I am currently seeing at the screen. This means I have more precious short-term memory to do whatever important task I am doing, like, programming.

Subjectively, touch typing is surprisingly comfortable. So even if I'm completely wrong about the above, I still feel better, and that alone is worth the investment.