A similar, non-LLM battle, is a global find and replace, but _not quite identical_ everywhere. Do I just go through the 20 files and do it myself, or try to get clever with regex? Which is ultimately faster...

I’ve just had to do just this, a one line prompt and one example was the difference between mind numbing work and a comfortable cup of coffee away from the monitor.

In this case LLM is probably the answer. I’ve done this exact thing. No messing with regex or manual work. Type a sentence and examine the result in a diff.