Cleary at 9 made a lot of sense during his early years as a half. He wasn't good at reading the game. His kicking and defence was always good, but creating tries was not easy for him.
He could have become a hooker in the mould of Cam Smith, controlling the game and kicking from dummy half to create field position. I always thought this high praise because Smith showed you could be as valuable as a halfback at hooker, if you are good enough. Smith is in the discussion for the greatest player of all time. It is no sleight on Nathan to discuss him becoming a hooker. Gower and John's both did a spell in that position because halfback skills are transferable.
As it turns out, Nathan has grown, learned and improved his skills as a halfback and right now there is nobody good enough to play half as well as him. Maybe, he can improve further and also be in the GOAT discussion. Time will reveal all......