| Inspired by a comment thread yesterday [1] I made this mini site: https://excel.secretgeek.net/ Reason: I often want to share Joel Spolsky's famous "You Suck at Excel" video tutorial with "important" business people inside the large enterprise where I work. But it would be easily misconstrued as trolling if I sent a business customer a URL that literally tells them, right in the heading, that they "suck" at excel. So, as advised by user @TuringTest (in the thread mentioned above) I created a mini site, on its own sub-domain, that is palatable to a business mindset, and brutally overlaid a heading that says "Secrets of Mastering Excel" right over the top of the "You Suck at Excel" heading. Now I've got something I can recommend to business people without causing disharmony. And I can leave a link to it in my email signature at work, to nudge my colleagues to improve their Excel game. [1] https://news.ycombinator.com/item?id=20418313 | 
Note: some of the information you linked is out of date, e.g. the linked summary says 'You have to sort the LookupLabels by name for match to work'. But MATCH() takes a third optional argument (match type) which, if set to 0, means you don't need to pre-sort your Lookup labels, and you have no risk of having an approximate match returned.
I wrote a short blog post with the Excel advice I most commonly give to colleagues, or when I've reviewed people's Excel sheets as part of a training session: https://www.encona.com/posts/excel-best-practices