>At what point would you need the implementation details of any of these to write code? ...literally any time you are performing a computation on a collection

>At what point would you need the implementation details of any of these to write code? ...literally any time you are performing a computation on a collection of items and care even the least bit about performance? It sounds like your bar for what makes "excellent code" simply excludes performance issues completely. That's fine if you're talking about scrappy startup devs who move from MVP to MVP. But when it comes time to turn an MVP into an honest-to-goodness P, you can't totally ignore the efficiency of your code. And you can't write efficient code without understanding the basic strengths and weaknesses of the data structures your programming language implements.