There’s just one problem with ur plan , a lock has to have ball playing skills and game skills , young johannssen and sione don’t have that experience yet .If Bird starts at lock, I’d like to see Sione Fainu (and/or Johannssen) on the bench to cover/share the lock role. Johannssen and Sione Fainu both have enough link playing attributes to their games.
If a half, centre or 2nd rower gets injured Bird could move to one of those positions during the game and Johannssen or Sione Fainu could go to lock.
Just look at other locks yeo , radley and others have a lot of experience, it takes time , not saying they wont work but I doubt it