It's probably getting to the point where we need an AUS v SAF thread because this discussion I think is heading towards selecting a team for that game rather than the 'RWC Optimum 23' discussion.
I think it's universally accepted that at some point prior to the RWC we are going to see Hooper and Pocock on the field at some time, but the division is with regards to whether it will be at the start of a game, the end of a game, versus a big gun team, or versus a minnow.
With regards to the selection of the best starting #8, that could be influenced by the choice of the flankers and/or the locks, and the prioritization of those choices.
If the starting locks are (as widely accepted) Simmons and Skelton, then we probably aren't going to see Palu & Fardy in the same back row. So if Fardy is 6, then Hooper is a better fit for 7, and McCalman would be the #8 (the incumbent back row).
Further, assuming the same starting locks, if Pocock is the preferred choice at 7, then Fardy may not be the best choice at 6. So we could even see Palu at 8 and the in form McCalman at 6.
Food for thought