It's a fair question, and in this particular case the math both light and irrelevant. But sometimes I see useful topics being discussed that are for whatever reason, marred by mathematics. Often these topics arent even particularly complicated, but the author's desire to give it (or themselves?) more credibility leads them to make it mathematical when it didn't need to be. See also, every discussion involving Haskell. A monad is just a Monoid in the category of Endofunctors, after all.

In most cases, especially cases of software engineering, as opposed to computer science, the math gets in the way of the point. It was never needed, it just served to obscure the topic. Plus, I'm not an engineer, and I'm not doing mathematics in my daily life. I don't think like a mathematician, I don't work with cardinalities, or set theory, or integrals. At most I deal with some multiplication and powers-of-two. Maybe a ratio here and there. If I was a graphics programmer, which I thankfully am not, I'd toss in some matrix algebra maybe. But my career doesn't involve anything requiring the use of ℝ. What it does involve, is thinking about composability of systems, debugability, simplification of processes, and otherwise making sure things work and can be understood by future maintainers. The article's topic is useful, but making things mathy for the sake of it is a navel gazing distraction.