Those pax were lucky there was a TrgCap down the back or they were going to ditch off the coast!
'Fraid that one is an urban myth that's been doing the round for decades!!.
The two instances in the last three years of QF having to go below minima in Perth have been handled OK, if you allow for the fact that they were allowed to blunder into Perth with no alternate by the (stoopid!!) Aussie rules!!