Just watched one of 'Delroy the sparks ' videos on YouTube, now the guy has many yrs more experience than me but I do question some of his techniques, however in this recent he does a proper Ze( ie removing main earth,) but leaves the installation live, is this a done thing?! I guess the risk in reality is pretty small for the 2 mins, but surely if your doing a EICR and you can't turn everything off its a LIM or by enquiry?