Hardwick is coaching from the bench so he can be in direct contact with the players. Paul Roos has the luxury of having many experienced players at the club. If Dea was at sydney he would probably do a long aprentiship in the seconds.
Circumstance at Richmond are different. Dea got a game, and he made some bad errors, but the sort of basic errors that you dont need someone to point out to you. He would have known he mucked up. wouldn't have needed to be told, they were pretty basic mistakes.
Dragging him would have been a real kick in the guts that he didn't need.