Bonsai makes some good comments and had me thinking about the scripture that was imbedded upon our minds in the 70s - The nations shall have to know that I am Jehovah. There was even a book about this but it led me to this thread and a comment by a guy called Jason Dulle
http://www.jehovahs-witness.com/topic/187201/nations-shall-know-that-am-jehovah-how-online?page=1
I loved his conclusion
<<In conclusion, although it is not necessarily wrong to say God’s name as Jehovah, by no means can it be claimed that Jehovah is the name of God that has only been restored to us in these recent times. At best Jehovah can only be claimed to be an acceptable way of pronouncing God’s name in the English language, and at worst it could be said to be a phonetic corruption of God’s name. The probable pronunciation of God’s revealed name is Yahweh.">>
He has a good point, you can't claim to restore something unless you know what existed originally, without having to make guesses or invent it.