"The3rd Earl Of Derby" wrote in message
. uk...

No, as the securing screws to back box will suffice.

Tsssss!

If the back box has at least one fixed (non-sliding) lug, then it's
considered that the fixing screws are sufficient to earth the box *from* the
accessory.

I wouldn't dream of doing it the other way around with a brass accessory.
IMO, the OP should earth the switch properly.

Will