I arrived at a very similar conclusion since trying Claude Code with Opus 4.5 (a huge paradigm shift in terms of tech and tools). I've been calling it "zen coding", where you treat the codebase like a zen garden. You maintain a mental map of the codebase, spec everything before prompting for the implementation, and review every diff line by line. The AI is a tool to implement the system design, not the system designe…
If you're this meticulous is it really any faster than writing code manually? I have found that in cases where I do care about the line-by-line it's actually slower to run it through Claude. It's only where I want to shovel it out that it's faster.