totally spot on. it would be negligant not to test between any metal parts withnig 2m.
e.g leaning on a metal water pipe/scaffolding/steel beam/washing machine casing, testing in a light switch. no cpc continuity for whatever reason. Measure live to earth, nothing, touch the pipe, 240v shock.
Any metal that's part of the electrical installation or extraneous can create a hazard. That's why bonding/earthing causes a danger and shouldn't be done except where necessary (class I equipment or extraneous conductive part that cannot be insulated) .
