Lateral movement is a huge weakness defending on an edge. The only players on the field who can 'get away' with having poor lateral movement are Props.
Defensive reads likewise. Whilst not as critical as it is for a centre, it is still VERY important for an edge forward.
2nd Row is arguably the most important defensive position in the game - along with Centre which IS more complex but requires less physical exertion.
I didn't say the edge though, You look at our starting team. The pack in particular all rep players so all pick themselves. All play big minutes.
Even Lindsay Smith can get through 50 mins, I'd add Garner to being established.
So it gives
JFH 50 mins
Leota 45-50 mins
Martin 80 mins
Kenny 80 mins
Yeo 80 mins
Garner 50-60.
So you are only looking to fill in the blanks from the bench.
Sorro can play middle when Leota comes off. Stay on to replace Garner. Leota comes back on.
JFH and Smith can share the other prop spot.
Leaves not many minutes for the other 2 benchies. Why not have 2 guys that offer something the starters dont.
If Smith is now moving to the edge during games and Sorro of course. Then you don't need an edge off the bench.
That opens up the options especially as teams are running with small middles through parts of the game.