While I don't fully subscribe to the oil-producer-conspiracy-theory, I do believe that there's a significant amount of smoke around the place.
It's entirely possible that crappy diesel is being dumped on us (meaning Australia) and the better stuff goes to places that need it, like Tikopia. In order to put the fear of God into us they keep yelling about how bad biodiesel is, and even get the dealers to chant it.
If biodiesel was good quality stuff, it would stop me from buying dinosaur, and the oil companies know this. They have a lot to lose in this game.
I certainly wouldn't go the home-made stuff, not in any new CR diesel, but I can't help but wonder if we're being blindfolded a little by companies that have everything to lose if people switched away from their products.