That is one subject that I just couldn't understand after discovering TTATT. But now it makes sense, and now I only use his name in a very specific or discerning way, especially in prayer.
For the believer, he is there Father. For everyone else, he is Yahweh. Now when I read the OT, it is clear, that those in God's favor were his "friends", and only his sons in the sense that he is there creator. But then Jesus introduced the Father, or we could say it more affectionately, daddy. Paul made that point when he used the expression"Abba Father".
Also, Paul used many scriptures that were originally applied to Yahweh, in connection with Jesus Christ. (This is what leads many to the trinity, but I have a different view). So now, God wants all attention to be on His Son. Now I appreciate scriptures like this even more today: Mark: 9. 7. "A cloud came, overshadowing them, and a voice came out of the cloud, "This is my beloved Son. Listen to him.""
What I never discerned before, is how each religion, has it's "main" doctrine they focus on. Seventh Day Adventists, Pentecostals, Christian Scientists, etc. For Jw's, it was the name, the name, the name, the name...... It feels so good to now understand such a simple concept. But until they wake up, this subject is beyond the grasp of Jw's.