I just tried Googling PID controller, and all I got was a bunch of computer circuitry.
The only other meaning I can think of is "pelvic inflammatory disease," which is maybe a little off, but it doesn't seem like it is wild enough to explain this story.
The only other meaning I can think of is "pelvic inflammatory disease," which is maybe a little off, but it doesn't seem like it is wild enough to explain this story.