The experiment setup is a little weird here. The participants were given a set of pre-created phrases to type/speech. At least for English, the phrase set [1] contains utterances like
"circumstances are unacceptable"
…which contains rare but in-vocabulary words. That makes it hard for keyboard input (hard for humans to spell long words, hard for touch input to predict unlikely words) but very easy for speech recognition (no other word sounds like "circumstances"). And that test set is so old that it's very likely that the speech recognizer from the experiment (or any state of the art speech recognizer) has already been trained on those sentences.
The utterances being pre-selected is also unfortunate. When users are given a sentence to speak ahead of time, they tend not to hesitate or stutter. They also speak faster than when they're trying to think of something to say on the fly, which is more typical of text input on mobile devices.
All that being said, it's certainly true that you can often input text very quickly with speech recognition, and it's getting better every day. :)