Not trying to downplay your grievances, but isn't this what [Skills](https://claude.com/skills) are for? After going back and forth on something like that, create a skill that's something along the lines of

`database-query-speed-optimization` "Some rules of thumb for using database queries:

- Use joins - Streaming results is faster - etc. "

That way, the next time you have to do something like this, you can remind it of / it will find the skill.