"Don't even try to understand" _never_ makes sense. In this context it's the mantra of idiots who want to put dog-slow abstractions into C++ (among others). You have tried and you understand micro-ops exists, that branch prediction exists etc. This information is useful when optimising.

If you never need to optimise C or C++ code why are you using these languages? Seriously? You've almost certainly got the wrong tool for the job. (Ok sometimes someone has made a legacy decision and you're stuck with it for bad reasons. Meh).

If you don't try to understand it, you won't know things like "Never use a linked list if you care about performance at all." Even Bjarne has twigged to that one (at last!). C and C++ are languages you use when you need performance, understanding the CPU as best you are capable is crucial for performance. DO try. In fact it's insane not to work on your understanding.

Don't even try to justify a statement of "don't even try to understand". It's wrong thinking from top to bottom. Here, as everywhere. No really.