The only issue I have with optimization porn is that it often handwaves away the time and thought that went into finding clever optimizations. In some cases it's clear how a problem can be better optimized. In many cases, it's not so clear. It takes someone experienced in development, an understanding of software and computational complexity, and the insight to see optimization opportunities or have used them before.

I also live in scientific computing world where the author lives and many other scientists don't appreciate the complexity of these optimizations the author hand waves away. It's easy to after the fact say, "well obviously look at this.." and show after the fact runtime performance improvements, it's another story to explain how you arrived at this, the time thinking about the problem sitting at dinner and before bed, while exercising or having coffee etc.

My biggest gripe with developers in this regard is how clever people like to act. They have a challenging problem and often spend significant amounts of time, then pretend like it happened over lunch. This does happen but from my experience, it doesn't happen regularly, not as many like to portray. You often iterate through several other optimization approaches aor ideas that fail or are discarded.

It's similar to when you see obnoxious compressed mathematical notation in a presentation where the author jumps through something they spent years on like it's trivial. If it was trivial, it wouldn't have taken you years and although a solution presented and checked to a problem is much clearer now than before, it's by no means obvious. This gives other professionals irrational expectations of resource allotment (in terms of your paid time) to solve these problems and makes your life more difficult than it needs to be.

Imagine if after Einstein spent time developing special relativity he skipped it all, hand waved, and said, "well clearly e=mc^2..." no--absolutely not clearly, but that's amazing insight.

Step 1: start with something grossly, ridiculously inefficient.

Step 2: Brag about your speed up