I thought I'd bump this and ping
@Frisbetarian, given that we had speculated about reasons for possible slumps and ongoing effectiveness earlier this off-season.
The article is a good deep-dive into his changed approach in the second half. I'm still sort of amazed that this kind of real-time data didn't make it to the hitting coaches, then to Yoshida, in the sense that it went on for months. Or that it got mangled or garbled along the way. Or that it was supplanted by the player's desire to do something different than what had led to a successful career in Japan (unlikely). Or that the Sox hitting coaches were (with the best of intentions) trying to tweak Yoshida's approach to mine it for potential (more likely.)
Assuming some of those scenarios above might be correct, it does make me wonder how large a sample size is required in the current org. to spot a problem and fix it. Even there caveats abound - I know some hitters can turn things around overnight with tweaks (e.g., Millar), and some can't or don't.
Regardless, I'm happy the article was written, as I think some sunlight on the issue might be good for the player - the takeaway is that he needs to go back to doing the thing he does well. Then maybe someone tinkers.