Fred99:
I'm pretty sure it used to be compulsory to pull over on the left before turning right when on the open road, and was a regular question in license tests when I first got my license in the '70s.
I think it may have changed when they changed the give-way at intersections rules (in the early '80s?) - now reverted. That was supposed to make it easier to turn right and improve traffic flow, but seldom worked well - especially when people turning left didn't bother to indicate.
I thought it was mandatory to pull left if you couldn't immediately turn right or if there was a car close behind on a narrow road.
My memory is that it's a fairly recent (last 10 years or so?) change, when the give way rules reverted. So it couldn't have been a question in 1970s license tests.