This looks exactly like how wiring is done in central europe. Except for the fact we only use Romex. And we usually plaster it over and don't just leave it exposed. *grin*
Here in Austria I have wired entire rooms like that. We once used to have some kind of flat Romex, (NYIF) (looked like zip cord, only double-sheathed and with more space between the conductors) which should ensure that any nail or screw driven into the cable wouldn't result in an arcing short. However, it costs 10 times as much as standard round 2 wire w/ ground Romex (NYM 3x1.5), so it starts to die out, which is a real pity.
