I'm not a sparky and I don't have an axe to grind.
However, to me it's not a very big deal to do all types of single an double phase electrical work in my home. (I probably could do three phase, but I won't because of the lack of current knowlege.)
I just apply some of the things that I've learned in high school physics and a few electronics classes. I've observed sparkies working and talked to them.
At our BORGs we have layman's guides to the NEC (National Electrical Code). If there is any confusion I'll just pop the cover off of the breaker box and observe how things were done.
There was a recent post about down lights. Evidently, from the description provided, the poster was trying to add a non grounded fixture to a string of grounded down lights. To me, it is not a big mystery even without intimate knowlege of the color code standards in OZ. (If the fixture is non-conductive, the fixture can't be grounded and a 2 wire connection should be acceptable and to code.)
I sense that in OZ there is a general fear of electrons by home owners and as one gets near electrons in large numbers, the fear increases. I'm really surprised at the number of times that forum members suggest that a sparky be engaged. I guess what I'm asking, is this "engage a sparky" philosophy a regulatory thing or a union issue or just ordinary Mushroom theory? (Keep them in the dark and feed them cow pies.)
I keep thinking that if somebody sits down and writes an electricity book for the home owner, there could be a huge financial rewards. Like a lifetime supply of tools and timber.