What a useless article, especially given the title. Here's all they have to say about the layout:

There’s some dispute over how and why Sholes and Glidden arrived at the QWERTY layout. Some historians have argued that it solved a jamming problem by spacing out the most common letters in English; others, particularly more recent historians, hold that it was designed specifically to help telegraphists avoid common errors when transcribing Morse code. Regardless, after around 30 test models, Sholes and Glidden settled on QWERTY—and changed the world.