Shanking is the "better player's" nemesis. I have been hitting some of the best drives of my life (beautiful baby draws right down the pipe and very long---300 yards with roll out) but I've been shanking the hell out of my irons. I think I know why, thanks to some info from an online article I found. Here is some stuff about coming into impact "under the plane" and the club shaft being "under the right forearm" as the player comes into impact which has been very helpful in my quest to be able to play a round without a shank. I have a stocky build (5 foot 10 and short arms) so I believe this means I am a more rotary (flat) swinger. Not sure if the advice in the article is helpful to upright (two-plane) swingers who might never approach the ball under the plane and are always (by default) battling more of an "over the top" tendency.
We're talking about an interesting concept today, and it's something that the average golfer doesn't struggle with, or that they strive to struggle with.
That is, coming too far from the inside at impact. Let's first define what that is, exactly. If I were to put a ball this way and look down the line, you can imagine that this is my imaginary target line - basically straight and down. You can almost see that this would be my target line. That's where I'd be trying to send the ball.
If I were to swing, to bring the club down and bring this club - now you can see it's underneath my forearm; it's coming in, this is what we would call too far from the inside or underneath the plane. As I come through, my club is actually approaching the ball from too in to out of an angle, or too far from the inside, so I would actually swing out to the right of the target line.