He'll probably go to the AL, become a DH, and hit 30 homers next season.
I doubt it, at least I definitely do not see another Jose Bautista situation
To what you alluded, I think Polanco has been damaged goods since the shoulder injury, as he's been struggling to hit .200 since.
Even before that, he flashed a nice power/speed combination, but never came close to being consistent enough to put it to full use, save maybe one or two seasons.
I just recall the immense hype when he was called up. He was supposed to be the next Bonds or McCutchen.
Apparently, the Pirates just fired their hitting coach, which probably has more to do with Hayes' lack of development than the terrible play of guys like Polanco.
I'm not really sure why they could not wait until the end of the season to do it.