Agreed. I generally feel pretty comfortable with letting LLMs implement stuff like individual functions or algorithms. But I feel like it takes some effort to make sure separate things stay separated... (I do think it also helps LLMs if the code to stays nicely abstracted.)

On the other hand, I do some stuff with physics simulations and LLMs will spit out arrays like

static constexpr std::array<int, Q> cx{0, 1, 0, -1, 0, 1, -1, -1, 1};

static constexpr std::array<int, Q> cy{0, 0, 1, 0, -1, 1, 1, -1, -1};

static constexpr std::array<real_t, Q> w{ real_t(4) / 9, real_t(1) / 9, real_t(1) / 9, real_t(1) / 9, real_t(1) / 9, real_t(1) / 36, real_t(1) / 36, real_t(1) / 36, real_t(1) / 36};

static constexpr std::array<int, Q> opp{0, 3, 4, 1, 2, 7, 8, 5, 6};

and it's like ??? I know what these are for, but I have no clue if any of the numbers are right :-)