As I don't have a camera phone it looks like I'm not eligible to do the work.
I wonder how many outlets in the U.S are wired with wrong polarity by non technical DIY types. The prevalence of non polarised plugs would also add to the assumption that the black and white wires could go either way round.
Just going on my small collection of U.S electrical fittings, it seems one is required to understand the meaning of the different terminal colours which are not the same as the wiring colours.
