That's a great way to put it . I wrote it down in lay men terms and stood in front of the smoker . I set P then set temp and waited . Wasn't getting to temp fast enough so I increased I until I ( me ) thought it was good . Turned it off cooled it down . Re started . Got to temp then I opened the door to lose heat and watched the recovery . To slow , so I increased D a bit at a time until it turned the element on almost as soon as I opened the door .
I ended up with a smoker that charges to set temp , over runs by 2 degrees , then cools to set temp ( does not go under ) and stays there . Open the door , turns the element on recovers fast with no over run .