That's a good point, though it's worth thinking about what would count as a demonstration. Pointing to a PR that an LLM helped with is not enough because you don't know how long it would have taken without the use of LLMs. The counterfactual never really exists. What is the hard evidence vim or emacs makes people more productive? Using git over svn? Using search engines? Over time, we expect people to use the things that make them more productive.
I would assume honesty, so someone showing with a blog post their incremental progress, prompting or code assistant use, rough time spent on each iteration... would be a great start.
I am not looking for formal study level of trust (though even that is frequently debatable), but multiple accounts of this where there is clear quality of output and significant (estimated) time savings would be wonderful.
I don't need much convincing that for many engineers, an LLM can bring incremental speed up (10-20%), though I think that really depends on the personality (eg. do you prefer to fix stuff not created by you or write it nicely from the start?).
