I hadn't thought about it this way before. Now that you bring up the analogy of a card trick, isn't that especially what happens at step C?
C. The God of the Bible is "Jehovah."
Psalms 83:18, bam! Or whatever verse in their Bible has the Name. It's like saying to a kid, "But, oh, what's this?!" and pulling a quarter out of their ear. "Wow, how long has that been there?!"
It puts the householder in awe of the JW for their superior Bible knowledge -- "Wow, these people knew the name of God, and I didn't ever know it was right here in my Bible! What else must they know?"
As a prerequisite, the person should be easily impressed (poor education) or prone to conspiratorial thinking ("There must be a whole world of secret knowledge that's been hidden from me all this time!").
Then we come to step D:
D. To be serving God "right," you must recognize Jehovah.
The reasoning point "How can you have a relationship with someone without knowing their name?" usually is all that needs to be said at this point.