Thanks for the recommendation, I'll have a look at his work, for sure.
Also I'd be curious to see that talk you mention, do you remember anything about it that could help in searching for it?
I think same talk but different recording: https://www.youtube.com/watch?v=MZUJsCh1wOY
I think around 1:08:30 onwards (maybe even before) the example I had in mind.
Also let me use this comment to recommand John Lakos, his talks, his books. He knows how to build large scale applications and if you saw his talk on the 'is_working_day' function (if I remember correctly) you know you were not overthinking.