[flyingron]

Put a nut on, but it should not be relied on to make the connection, the twisting does that

Not this again. The above is patently untrue. The listed fastener is required to make a gas-tight connection. Twisting alone will not do this.

 

[flyingron]

I believe California has a version of the NEC. Canada has the CEC.

Nope, California also has the CEC: California Electrical Code. It's a rather formal mod over the 2017 NEC .

 

[flyingron]

Or you have one of those plastic boxes (popular in Canada but not in the US for some reason) that has the strap the runs up and provides a means to ground the device screws.

 

[flyingron]

The only mod to the 2017NEC is the inclusion of the CA Energy Code. Otherwise it's 2017NEC word for word ,

Nope, in addition to the energy code stuff there is some additional inclusions like exceptions for switches in for call systems in showers and knob and tube wiring.