I can't see how any electrician who had actually read and understood the regulations could believe that there was a requirement for your covers to be earthed - and I would hope that they would also have enough understanding of electric principles to realise that it is, at least theoretically, preferable (fractionally 'safer') that they should not be earthed.@EFLImpudence, I don't 'seem to think' anything of the sort, I came here to ask, from a position of ignorance, if the fitting met the regulations, as I had read (on an electricians forum) to the contrary. It would seem the short answer is that there are as many opinions as there are electricians!
I can but presume that those who suggest that earthing is required must be thinking of switches which themselves have metal faceplates (and definitely do need to be earthed), rather than of things that are merely metal covers over plastic switches.
Kind Regards, John