What you're forgetting is that Latu Fainu is TWENTY. He's not being groomed into a lock - he's being given time to develop his game
Even if he plays second fiddle the entire of next year, he'll be 21 and an extremely young half.
Tigers fans seem to think it's normal to play kids at 18 who have no experience playing against actual men. Look at Storm - they leave guys in reserve grade until they're 21/22 and ready to play grade.
As of right now Latu has practically never played 80 minutes in first grade. He's barely even played it in reserve grade. Give him time to develop!