You know, I see where you're coming from, but for me, it's never been that clear cut. Like last month, I had this bag of beans that just wouldn't play nice with my usual coarse grind, no matter how long I steeped it. Switched to a medium-fine grind for three minutes and it was like a whole different coffee. So I'm starting to think the beans themselves call the shots, and we're just adjusting grind and time to match. It's less about one rule and more about listening to what each batch needs.