Yes, he took an unsettling step backwards in 2014. But there's a reason why Christian Hackenberg is the number one overall pick on some 2016 mock NFL drafts- when given time in the pocket, there aren't many quarterbacks- college or NFL- who can make the kinds of passes Hackenberg is capable of.
For most of the 2014 season, Hackenberg was forced to keep his eyes on the numerous defenders sprinting his direction rather than looking for open receivers. This caused a major setback in his mechanics, and caused him to short-arm many passes, even when he did have time to follow through.