I went solo in about 52 minutes......
(in a glider at summer CCF camp at HMS Condor many moons ago)
Interesting thing was, I only ever flew right hand circuits over the ski slope.
So, as I tell powered students today: I went solo in less than one hour, but I never knew how to do left hand turns! (of course, it was a tandem glider, so unlike in a side-by-side the view would be the same whatever direction the turn). And we try to be a little more thorough.
Of course the RAF - often hailed as "flying instruction par excellence" here - also had the commercial benefit of Crown Indemnity!