Sometimes it seems as if Prime Minister Malcolm Turnbull has an “on/off” switch, and when it comes to announcing government decisions that contradict his previously held convictions, the switch is firmly set to “on”.

That’s how it was when Turnbull swept into the Blue Room at noon on Tuesday, checking his watch on the way in, to announce the government’s decision to have a second go at passing a compulsory plebiscite on marriage equality and that the government had found the technicalities it needed to run a non-compulsory postal plebiscite without having to go through the obdurate Senate.