Least dangerous only within the limited context you defined of compilation errors. If I hired a programmer and I found whole libraries they invented to save themselves the effort of finding a real solution, I would be much more upset than if I found subtle logical errors in their code. If you take the cynical view that hallucinations are just speed bumps that can be iterated away then I would argue you are under-valuing the actual work I want the LLM to do for me. One time I was trying to get help with the AWS CLI or boto3 and no matter how many times I pasted the traceback to Claude or ChatGPT, it would apologize and then hallucinate the non-existent method or command. At least with logical errors I can fix those! But all in all, I still agree with a lot in this post.