There's ball position in terms of forward or back in the stance, but often times the more overlooked ball position is whether it's closer to, or farther away from the feet.
Just the other day a guy who is a 5 hcp was shanking irons. The shorter the iron the more he shanked. He was at wits end trying to figure out why he kept shanking. He asked me to meet him on the range before the 2nd round of a tournament (club tourney) to see what the heck he was doing wrong. Well, it took about 2 swings to see that he was throwing the club head out on the downswing. Just about that time a pro teacher at the club stopped by and tried to help. At this point (and I kept it too myself as the pro was there), he looked too far away from the ball).
The pro placed balls on the ground such that he was to hit the object ball without hitting the ball adjacent to the object ball. That didn't work as he hit the object ball and a third of the other ball. Still no luck. The pro departed to meet a student.
So I jumped in and asked him to assume his normal setup position to hit a ball (with a ball in front of his club). He set up as usual. BUT, then I asked him to swing and COMPLETELY MISS the ball to the inside, or move the club path closer to his feet. On the first swing he "ticked" the object ball with the toe of the club. The next time he successfully missed the object ball to the inside, and with about a half inch to spare. SO, he went from throwing the club out and hitting two balls to missing the ball to the inside? Hmmmm. How could such a reversal occur in about 4 minutes??
Then after 10 or so "misses", I had him move the ball about a club head closer to his feet. Next shot...perfect. To get the club path closer to his feet, his lower body HAD TO engage first to start the downswing. What was happening, and it happens a LOT with shorter irons, is folks will position the ball too far away. They don't adjust for the length of the club and use a 5 iron-like setup for a shorter/short club. Thus, they're too bent over at address, too far away from the ball, which makes it very easy to "throw" the club out at the ball. When the ball is too far away, the brain knows it, and (I believe) the brain calls upon the right shoulder to "get the club head out to the ball", or an over the top, shoulder-driven swing.....the opposite of a lower body initiated swing.
The point of the drill is not just to cure shanks. This is a good check for all irons and even the driver. If I can setup to the ball with a driver, then completely miss the ball to the inside, then chances are I am standing too far away. The drill procedure is to keep swinging to see just how close one can get the club path to their feet. The only way to get it as close as possible is with a lower body initiated downswing.
I pretty much guarantee some folks out there will discover they've been standing too far away from the ball after trying this drill. And once one figures that out, then they'll start to understand why they they tend to come over the top. When doing the drill it's pretty amazing how quickly the brain figures out that the only way to get the club path closer to the feet is by using the lower body to start the downswing.
Try it and see what you think. Oh, and for the guy who was shanking irons? He shot 72 with 3 birdies on Saturday.
....to add to the above...some folks will advise someone who is shanking to move the ball FARTHER away from their feet. This only makes things worse. The closer the ball is to the feet the more the lower body will want to, or need to engage to hit the ball. I think of this as "closer = more lower body", "farther = more upper body".
Nice post! Even though you say "the point of the drill is not just to cure shanks", you are still indeed our resident "shankbuster".
I sure hope your friend gave you a "coach's cut" of his Saturday winnings!