thanks for taking time & effort to respond Pirate, my query relates to the need for E1, E2 etc, if the circuit was "floating" there would be no return path via earth to cause electricution, merely a live chasis which would give a minimal shock I would think, similar to birds sitting on power lines. As you say the breaker may not activate but with no return path is this an issue, most likely the appliance will have failed & the fault investigated. The breaker would still operate in event of a short circuit most appliances these days are only 2 conductors anyway.
as to cost, not providing an earth has got to be cheaper
