I too have a question about the hand line, especially as it comes to adress vs. impact.
As of late I've been hitting most iron shots on the toe side of center (maybe a half a ball). I'm almost certain it has to do with steepening the shaft.... (THE NEON GREEN LINE IS AN OVERLAY OF THE SHAFT ANGLE AT SETUP)..
Red line is representative of the HAND LINE AT ADRESS. I've watched a ton of swings on YouTube, and EVERY pro is returning the hands to that line or just fractionally past it (like Rory above). My hands though are way out beyond it and much higher.
Every thing about that screams Sh*nk.. but I've read the shaft steepening is compensating move, and actually causes to hits.
So... How the HELL do you keep your hands at or inside that line? Super tough concept for me to grasp, especially battling toe contact?? It seems id be even further away from the center of the clubface..