Why Has Mike Trout Gotten So Many Walks Lately?

It is 26 in his last 20 games (and it was 26 in 19 games but he got no walks today). I am curious if anyone has a reason. He had 51 BBs in his first 102 games this year and had 67 in 139 games in 2012. And another question: is a walk to Trout more valuable than average due to his speed?