From around April through October, the production for Naruto Shippuden takes a hit due to resources being diverted to the annual movie that debuts in the summer. The best example of this is during the Pain arc (summer of 2010), which had high expectations given the source material only to have a fairly mediocre adaptation in the end. The only outliers were episodes 166-167, the latter drawing much controversy thanks to its fairly ambitious and unrestrained approach.
The summer of 2011 was not bad in comparison. Partly because there was a filler arc in place of canon material, but also because of the promotion of Studio Pierrot animator Masayuki Kouda (above) to the regular rotation of animation directors. Kouda joined Studio Pierrot in the early 2000s where he started out as an in-betweener on shows such as Twelve Kingdoms and the original Naruto series. He made his animation director debut in late 2010 on episode 180 of Shippuden where he was paired up ex-Kyoto Animation animator Gorou Sessha (storyboard/episode director).