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A. Set I and D to zero

B. Adjust P for 1/4 wave damping , Adjust D to improve response , Adjust I to correct Offset

Repeat B. Repeat B. Repeat B. Repeat B. Repeat B. Repeat B. . . . .

Depends on your system!!! If you online tune and accidentally set P a little too big it is quite easy to set off an unstable oscillation and depending on your application can get a rather expensive earth shattering kaboom...

I usually end up saying "Screw it" and adjust the value under control to remove half the error at each timestep. Surprising how often that's good enough.

Many processes like temperature controls want to settle, you just have to help them out a bit. Applying a full PID algorithm to every control problem is a bit like using TCP/IP to solve every networking problem. It will work, but you'll often do better with a domain-focused solution.

Temperature control problems are only first-order (heat->temperature), so they're much easier to control than a second order system like force->velocity->position.

Yep, totally. Motion control would be a different case altogether. Zeno's Paradox was supposed to be a puzzle, not a solution.

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