Dave, I just got around to listening to AH#14. You were talking about the restrictions on working on electrical (mains) power in AU, and asked what it was like in other areas...
I've been building an In-Law apartment attached to my house for about 6 months. About a month ago it was time to deal with the power. The existing breaker box on the house was only 100 amps, and only provided 14 circuits. There were also some horrible (scary) changes made by the previous owner. I had corrected them when I moved in a dozen years ago, but now it was time to replace the whole thing.
Long story short; I got a permit from the city ($125), started at 6:00am by killing all power to the house, ripped out the old box, opened up the wall, installed the new box (200 amp, 44 circuits), wired it all up and had the power back on by 4:00pm. Note: bending 00 gauge cable to fit in the box was a bitch! The city inspector came out and did a 5 minute inspection and signed me off. Done.
To your question, I have no formal electrical training or certificates. Here (in Arizona anyway) if you own the house you can undertake virtually any kind of repair or construction you wish -PROVIDED- you get the proper permits from the city, and you pass the inspection of your work. Now I think it's safe to say that virtually no one actually does this level of project on their own, but the thing is, they could.
Here's the picture I posted to Facebook of the work...