Many scholars have pointed out that the pronunciation 'Yehovah' for the Creator's Hebrew Name יהוה is grammatically impossible in Hebrew.
 
Nehemia Gordon offers a very attractive 'explanation.'  He claims that the Name יהוה is a combination of three Hebrew words: 'Hayah,' 'Hoveh' and 'Yihyeh.' When combined these three verbs supposedly make 'Yehovah.'

So, if Nehemia's claims about the etymology of 'Yehovah' is correct, it would make 'Yehovah' a grammatically possible Name. However, if Nehemia's claims are untrue, it would simply reconfirm that the pronunciation 'Yehovah' is incorrect.