[oh_my_goodness]

"A good typist (which I'll call 100 WPM, a point beyond which I diminishing returns make further improvement less important) can do the writing-is-thinking process 4x more in the same amount of clock time as a 25 WPM typist."

...if they spend all that type typing.

[Joker_vD]

You see, if you type faster that you think that means that you're typing out things nobody's thought about — which is what it means to be a genius.