Dialing in by grind

A recipe gets you to the neighbourhood; grind gets you to the door. Dialing in is a loop, not a leap: brew your reference recipe, taste it honestly, move the grind one step, and brew again with everything else frozen. The freeze is the method — if two things changed, the cup cannot tell you which one worked.

One step at a time feels slow for exactly two brews. Then it becomes the fastest route there is, because every cup teaches you something true.