I think the “What it won’t touch” section shows why the entire concept is unsound. Here it is with a different first sentence, and (other than the third sentence no longer matching erm’s reality) it’s perfectly coherent: > It leaves um , uh , er and elongated versions ( ummmm , uhhhhh ) alone. Those sound like fillers but they’re doing real work in the sentence, and cutting them automatically would change what someon…
>> It leaves um, uh, er and elongated versions ( ummmm, uhhhhh ) alone. Something's already gone wrong here. Uh and er refer to the same sound. Uh is the American spelling. Er is British; to them a following "r" like that is just a kind of vowel.
(Also, in case it wasn’t clear: I was quoting from the start of the article in that sentence.)