I'm gonna be the contrarian and say this is mostly fine. We can research the proper way to do things, or use code review to teach about the proper ways. But thi

I'm gonna be the contrarian and say this is mostly fine. We can research the proper way to do things, or use code review to teach about the proper ways. But this can lead to code shaming and a fearful environment where people second guess themselves and spend a lot of time chasing a perfection that doesn't move the business metrics. In this case, doing the join manually isn't a huge deal, chunking isn't a huge deal, parallel requests isn't a huge deal. But "concurrent limit reached" is the point in this story where Bob should have put on the thinking cap and reasoned that "this shouldn't be hard, other people do things like this with bigger datasets all the time, I wonder how". Before that point it's literally just a matter of changing a couple lines to solve the issue. So what? After that point however, it's starting to affect the overall design around it in harmful ways, and turning the issue into a bigger one.