A year ago, the Dallas Cowboys had one of the best offenses in football. Armed with arguably the NFL's best offensive line, sensational rookies Dak Prescott and Ezekiel Elliott at quarterback and running back, and weapons all over the perimeter, Dallas steamrolled over the league, ranking fifth in yards and points and third in Football Outsiders' offensive DVOA. Beyond all the talent Dallas had, the most important factor in their success was the job coach Jason Garrett and offensive coordinator Scott Linehan did putting those players in position to succeed. This season has gone quite a bit differently. Despite returning largely the same personnel (Dallas did lose right tackle Doug Free to retirement and left guard Ronald Leary to free agency, then saw Ezekiel Elliott get suspended for six games), the Cowboys have fallen off to 14th in yards, 12th in points, and 10th in DVOA through 15 games. Prescott has undeniably regressed. Dez Bryant is having his worst season in years. Cole Beasley has basically disappeared from the offense. Dallas seems to have no element of explosion to its offense and has also struggled to put together sustained drives at times. The culprit, according to multiple players, is not the injuries, the backward step the offensive line has taken, or the lack of chemistry between Prescott and Bryant. It's predictable play-calling.