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What indicates there's still power? Even if you've isolated a circuit then touch a neutral & earth it will trip the main RCD on the consumer unit (I think).
inchpincher-
The individual circuits Neutral and Earth are connected in a typical RCD setup. So touching Neutral and Earth with only the Live disconnected (i.e. single MCB switched off) will cause a parallel path to Earth from the Neutrals on the other circuits. This disrupts the balance in the RCD and trips it.
The current regulation is leaning towards RCBO's which protect each circuit individually, they are more expensive so they're not that popular with jobbing electricians who like to stay competitive on price and don't want the material costs eating into profits. They should be the future though, it's probably only a question of time before they're regulation.
Airhead
I'm a big fan of centrifugal, err...
Bathroom extractors that actually do something are a revelation though, really.
Question for you as an ex-electrician or someone else who knows this stuff: why when I turn off my lighting ring on the fusebox is there still power in some of the cables, even when the circuit is turned off and the lights don't work?
I need to move a light switch sightly and was hoping not to have to turn all the power off.