Although a model would likely need a different guide, aimed at its particular issues.
Have you... tried having Claude be concise and easy to read (for more 2 sentences) ? If not, when you'll arrive at the despair state, search for "claudism"^^
Yes, I've been doing this since Claude 2 (1.x really).
Do you have resources and examples to share? More than the previous versions, Sonnet/Opus 5 are very resistant to being concise.