Facts:
You need to understand what it's doing to keep it on track or a lot of time to head down all of its dead ends.
You need to understand your intent and project in order to recognize that it's hallucinating.
When it magically decides variables or other factors need new unused names while mid way through any project, you have to watch out for that- you have to be able to audit everything it does and constantly restate the whole project in chunks.
We saw the one off example of a coder beating an LLM at code production recently.
I don't expect LLM coding or reasoning to be good for a while.
Apple iOS users outside of the EU are familiar with this too.