The protection thing is predicated on the idea that Mookie is now getting better pitches to hit. That's something that should be detectable in the pitch data. I don't have the data so I can't comment on that.
On an 'anecdotal' basis, though, from reading game threads, what some posters were saying about Mookie when he was in a funk was that he was getting good pitches and not swinging at them, his approach was too passive. Again, that would be in the pitch data.