Start with these numbers:
5.8 yards: C.J. Anderson's average yards-per-carry against Carolina with Andy Janovich on the field.
3.4 yards: Anderson's average without Janovich.
Four and a half years ago, I wrote a story with the headline "Death of the Fullback" after the release of Spencer Larsen following the 2011 season. The Broncos would use Chris Gronkowski sparingly at fullback in 2012, but aside from his work and a brief Jacob Hester cameo late in that season, the fullback vanished from the offense for nearly all of the next four seasons. The 2013 and 2014 seasons passed without a fullback anywhere on the roster; whenever the Broncos needed someone for a fullback-type role, they would call on a tight end like James Casey or Virgil Green, or a lineman such as James Ferentz or -- memorably -- Mitch Unrein.