That's cause most of the 10s should be able to cover the inside centre so coaches pick an extra outside back (11,14,15) on the bench. Not cause Paisami is a hell of a player. Actually is the only option at 12. Stewart with 2 good games could be the new starter 12, that's how low is the bar nowadays. And I hope he's the new Michael Hooper, a guy who took his first opportunity in the Rugby Championship with 4 hands and after that, never left the team. That would be great for the Wallabies, if Stewart becomes in a top class inside centre