I used to work at the Training College in Adelaide where you will do your 4 weeks of "Finesse" training if you get in as a SO. Back in the late 80's & early 90's, there were people getting in with 1200 hrs total, piston only.
It all depends on supply and demand at the time. Currently there are lots of qualified people so the "Unofficial" experience is more like what they are stating above.
But to answer you original question, It has been done before.
WP