Replacing Kurios with Jehovah 237 times in the New Testament certainly legitimizes, in the mind of Witesses anyway, the Watchtower's emphasis on the name Jehovah.
Sadly, over half those insertions are not based on quotations from the Old Testament where the Tetragrammatton is found. So the majority of replacements are designed simply to support Watchtower doctrine.
It's rather revealing that they ignore certain NT quotations from the OT where the Tetragrammatton is found as in Philippians 2:11 which reads
And that every tongue should confess that Jesus Christ is LORD, to the glory of God the Father.