According to an IBM-University of Michigan study [link to PDF], when transcribing, those using a traditional hardware QWERTY keyboard type at an average rate of 33 words per minute. This means that YouTube user "konceptzoflife" is 152 percent faster than the average typist.
The only thing is, he can do it on his iPhone.
The 83 WPM, which is the fastest I've seen on an iPhone, is still markedly shy of hardware QWERTY keyboard record holder Barbara Blackburn. The late Blackburn, whose fame made her a guest on Late Night with David Letterman (when he was on NBC after Johnny Carson), can maintain 150 WPM for a full 50 minutes, and can top out at 212 WPM.