When is a jumping player deemed to be in touch? If a player jumps from the playing area and knocks the ball back into the playing area (or if that player catches the ball and throws it back into the playing area) before landing in touch or touch-in-goal, play continues regardless of whether the ball reaches the plane of touch.
That effectively means he is not in touch until he lands there. Conversely we would expect a player jumping from touch to be in touch until he lands in the FoP.
That appears not to be the case. This was such a deliberate technique it must have been designed and taught after consulting the refereeing gurus. The inference is that if you jump from touch and the ball has not reached the plane, it is play on. Moreover if it had reached the plane, the catcher was not the person who put it there. Win-win.