Im still not sure whether you don't understand what you are talking about, or are self-delusional about YOUR abilities (in that you know better about ATC than actual controllers).
the Class D would immeasurably drop in safety when the single controller in the tower was attempting to control circuit traffic close to the airport as well as separating an IFR and VFR enroute aircraft possibly twenty miles away in the C airspace above
You have repeated this lie, this untruth, many times, and had it explained to you before.
Some of our controllers maintained that they had some type of super-human abilities when compared to controllers in other countries, and they could indeed do this extra workload without any reduction in safety
Another BLATANT lie. Controllers in oz have never said this. They have merely pointed out that if you add VFR workload in oz , it is an enormously small workload compared to if you added VFR workload to towers in the US of A, where there is ****eloads more VFR traffic, and they couldn't do it without many more controllers. Read peuce's post. If there were a very large number of VFRs operating around an airport (like they have in the states) then more resources would be required.
"A lie told a hundred times........" And you certainly like telling them a hundred times, Dick.