I was thinking about the 'wider' training squad yesterday, I guess who is in it would depend on what they are doing while they wait for the rest of the players to join them. E.g. I doubt the set piece is high on the agenda, there wouldn't be a front rower across both squads that is likely to be in the final Wallabies squad (except maybe Horton as the 3rd hooker). However, there a lot of locks, a few back rowers, a couple of halfbacks, a fly half, a couple of centers, a couple of wingers and maybe a fullback. So I'm guessing they are working on the backline and breakdown for this week, probably mostly skills based, and select some other players to run opposed and to fill in the gaps and get some experience.