Broken spark plug in head procedure.

[DieHarder]

Just my opinion. Sparkplugs diagnose problems better than computers. They can predict an upcoming issue.
I recommend pulling and checking gap and residue on them as often as you change your oil.
I call this an, "ask the car how it feels" checkup. It will speak volumes to you about spark duration, air / fuel mixture, and so much more.
Enjoy the cars.

Good practice. I would be very surprised if you ever have a frozen/broken plug issue.