I'm constantly amazed by how blasé electricians are with regard to live voltage.
I'm used to mixing with software developers, who have a healthy fear and respect for "hardware", or physicists who're a very cautious bunch on the whole.
A week or two ago I developed a leak in my flat's roof, which lead to a small amount of minor water damage and a failure in my lighting.
I've had a couple of people out to look at it, and they all seem quite happy poking around with the (potentially soggy) electrical cables without me disconnecting the ring / main supply.
Still I guess they must know what they're doing; they've not previously been killed ...