I have a question I've always wondered about:
In the US NEC, ground wires must be pigtailed. This is acceptable in Canada too, except that in the CEC (Canadian Electrical Code) it is also perfectly acceptable to terminate ground wires on the screws in the boxes.
So if you had 2 NM cable in a box, you can put one ground wire on the screw and cut it off, and the other one can run through the screw and attach to the device.
Seems to be pretty common to double up grounds on the screws too; a straight through connection on each side of the screw.
What is the just justification in the NEC for not allowing this? If there is one. Or, just any general opinions?
