Well Police can't weigh you but Transport can and it would be interesting to see as I think with most set ups that are over weight they are more than likely over the GCM which is what would attract the fine not so much the individual trailer or would you cop a fine for trailer and tug as most forget about the tug, I wonder if to make enforcement easier that all axles will have a official tag displayed that states the gross of that axle then you would just have to weigh individual axles and not break up the combo.
The regs have always been there it's just that bringing them out into the open sells magazines and gets everyone talking and eventually the pollies will make the extra people available to write the tickets but it's not new just another reg that laid dormant until someone spotted it and started yelling.