Really though Panthers were just copying..
Souths with Burgess and Burgess and Burgess used that highly mobile front row as a playmaking pack.
Sharks had some pounders like Gallen. But they also had Luke Lewis who was a 2RF who did play in the halves, along with Heighington and other mobile guys in the front row.
Honestly it's a good idea and one we should copy, but notice the difference?
Penrith, Souths and Sharks had big bodies play a mobile game.
With Galvin were talking someone who is fit, but not a big body like Lewis/Burgess/Yeo.
^Maybe you can credit Sheens with a bit of the above. Heighington, Ellis, Fulton, etc playing a high pass game as mobile 2RF was something he started. Really when I think about it more, Kite/Watmough at Manly seemed to perfect it better.