I thought fat tony would joke about the chin other way around. Didnt fat tony send out christmas cards with a picture of him in a bathrobe to all the genovese guys and the chin didnt mind. Fat tony was as powerful as a mob guy can possible get, his decision on matters was considered law and he was a worth millions. He didnt need to block the rise of the chin from being boss because he was an old man and the chin was groomed his whole lcn life to be adventual boss.