As far as the Queen intervening in 1975, it's true to a point. The Judges on the High Court were all old conservatives who despised the elected Labour Gov. who brought in massive sweeping changes like land rights for Aboriginies. They found an ancient law that gave power to the Queen's representative the Governor General to dissolve parliament and appoint an interim Government in times of crisis like when the Senate cannot decide an issue. Guess who they chose? The conservative opposition. There was massive protests and the GG died a despised rambling drunk. That legal loophole has been patched.
Thanks doofdaddy, i didn't know the details just remember it being mentioned when i was at college many years back.
Paul