I don't think it's harsh. It is a reasonable question to ask. Academia is rife with people who have never worked in the industry, completely disconnected from reality.
From what I understand reading the course outline, this is an introductory class. Foundational material in a subject is often "completely disconnected" from the reality of the discipline. If I was an engineer taking a first course in integral calculus, should I worry that my teacher may not be a seasoned practitioner, or should I worry that they are good at getting me to understand the fundamentals? I can definitely see your argument if this was a professional practice class, or something vocational, but it's a 100 level CS class.
I think you should worry. One of my math professors taught us how factoring to a(x+b(x+c*(...))) is a great optimization in an introductory class, because he had no idea about CPU pipelines for example.
I'm working on a project where the evaluation of a 4th degree polynomial is on the hot path. My micro benchmark (evaluating two polynomials + little bit of addition) shows that using simple Horner's rule is already somewhat faster, and implementing Horner's rule with fused-mul-add is more than twice as fast.
I would be very nervous about the integrity of a bridge designed by engineers whose sole source of knowledge was a teacher who has no experience in construction or design of bridges. That’s even considering the engineers may rely on industry standards bodies like AASHTO that prescribe much of the particulars of a design.
To my knowledge, no such standards bodies exist for software, making the designs of pure theorists all the more concerning. Maybe FRAMA-C? I’m not sure if that’s equivalent to AASHTO LRFD. Given that end users have almost no way of evaluating the safety or quality of software, similar to medical or legal counsel, I would think that there is an obvious need for some kind of regulatory body. Celebrity-bloggers seems like all too common a source of best practices.
