It seems like the article is trying to make the case that in romaji, you can split the letters and isolate the vowel (e.g. the asterix in the article's conjugation).
But we were simply taught to change from the う- row to the い- row (u- row to i- row). I switched to Japanese to illustrate that you can make that statement even without romaji. In that case, it seems like basically the same thing?
As an anecdotal point, my class was mostly non-english speakers and I didn't find the above to be a sticking point for my classmates. The real sticking points were messing up the ichidan verb exceptions (ichidan verbs that look like godan) and conjugating the correct form for the different grammar points. Te and ta form were also a bit tricky. But the article doesn't seem to offer anything new to help there.