#1
The screws on a humbucker are for what? What happens if I screw them?
You stole my heart!
You ran away!
Now I'm heartless!
So fuck you anyway!
#2
Just like the whole pickup can be raised or lowered to fine adjust the output - in other words, closer or further from the strings - the individual pole pieces can be adjusted for the same. Especially useful when there's a small radius fretboard so you can better match to the individual string heights.
#3
Oh cool.
What would happen if I took them out? Lol, I'm not going to, just curious.
You stole my heart!
You ran away!
Now I'm heartless!
So fuck you anyway!
#4
I think he means the ones in the bobbins.

EDIT: Misread the post, nvm. What he said is right.
R.I.P. Les Paul, 1915-2009

A man chooses, a slave obeys.
#5
The screws give you control on each string's individual output. Raising them increases output, and lowering them does the opposite.
#6
Gotcha. I'm kinda forced to screw with it now.
You stole my heart!
You ran away!
Now I'm heartless!
So fuck you anyway!