If you didn't know, the Mariners are 6th in IFFB% in addition to being 5th in LD%. Why is this? I think it's the side effect of the 'killer' swing, you lose bat control, the bonus in force is subtracted from agility, keeping the batter (and particularly Ichiro) from making a swing more appropriate to the angle of the balls flight and instead swinging purely with intent to harm. In addition, every one has noted Ichiro standing at the back of the box instead of the front so that he has the extra millisecond, but the pitch gets the extra millisecond as well, and pitchers with nastier stuff have that extra break space. In effect, meatballs, Ichiro now has all the time in the world to react to, but fastballs, splitters, cutters and sliders with late break get an opportunity to break harder on him.