w_tom wrote:

Fine. Now show us how an RCD would not provide a wet human in a
bathroom with protection.

An RCD protecting a circuit feeding equipment in a bathroom would not
protect someone from the effects of contact with metalwork earthed via
different paths which could, due to faults
_elsewhere_in_the_electrical_installation_, be at dangerously different
potentials. This is why BS 7671 mandates the use of local supplementary
equipotential bonding as a primary safety measure.

BTW, what is BS7671; what does it define - or its title?

BS 7671 _is_ the UK Wiring Regulations:

BS 7671:2001
Title: "Requirements for electrical installations."
Subtitle: "IEE Wiring Regulations. Sixteenth edition."

BS 7671 is to a significant extent harmonised with European (CENELEC)
and international (IEC) standards (IEC 60364 series and CENELEC HD 384
series).

--
Andy