Even if some people post comments like that as a trope, some - if not many - post them sincerely. I think the original criticism makes perfect sense: an article for beginners might better benefit its readers if it offers just a simple sentence or even link that briefly explains what the topic is before delving into its details. I personally have read a number of articles where I've encountered this problem, despite my familiarity with the given topic.
Also, I think it benefits the HN community at large if we try our best to read people's comments in a positive light, within reasonable, and encourage giving and receiving constructive criticism from one another.
Speaking of bad faith, how about some benefit of the doubt? My comment was not meant to be critical, but helpful for others who might have that same nagging question in the back of their mind while they read the article: "But what are CTFs"? It might be obvious to you, but I couldn't tell if CTFs were some RE tool, a part or category of ELFs, or some other binary format (and I do indeed know a thing or two about Linux/Engineering/Electricity) Probably a better comment could have been "Great overview, very helpful, but I had to google CTFs: Capture the Flag". Let me know if that would have set off any other "hn trope" triggers for you....Sheesh