[vjcapron]

Pay attention to the pic on the right. The clubshaft is definitely under the heelpad of the left hand.

Try this test:
With only the left index finger and the heelpad on the clubshaft as Hogan demonstrates above, you should be able to pull fairly hard on the shaft or clubhead with your right hand without the club coming loose. You should have a definite "I got it" feeling with just your index finger and heelpad.

P.S.
Was Anthony Ravielli the greatest illustrator of all time, or what? Look at all that detail in black and white. It still amazes me every time I bring out my copy of 5 Lessons.