Walter Martin was just trying to jerk the JWs chain!
I heard him describe this "prayer" technique in one of his audio tapes, it is quite an amusing story the way he tells it.
He probably did do something like that at one time.
In the story, the JWs said they could not pray with him, but Martin went ahead and started to pray, and when he used Jehovah's name, Martin said the two JWs at his door automatically bowed their heads! Talk about a conditioned response!
--VM44