This topic is really old and therefore redundant as you can see from the image below, I've already got what I was requesting back in time:
As the game engine does not support another point of articulation yet the dolly on the trailer does not turn. Driving such a combination is still very possible in-game (you can find videos of it on my YouTube channel).
And what comes to your long post, all I can say that you are talking of Australia apparently as in Europe and especially here in Northern Europe the laws differ quite a lot. So a lot of those things you said do not apply in Europe.
Even though the majority of the ETS2 community calls the combination in the image below a "tandem" that is not correct.
In real life it is simply a "module combination" consisting of a rigid body truck and a middle axle trailer.
However, in Scandinavia and Finland combinations such as B-trains and other 25.25 meter long combinations are more common than standard semi-trailer trucks. Here is an example of a real life full-trailer truck which is the most common type of truck and trailer combination here in Finland.
EDIT:
Apparently most of the relevant images featured originally in the first post do not show or exist anymore as the topic is so old.
