Heavy I puts a tight end on each end of the line, one receiver off the ball to the right, and the fullback and tailback stacked behind the quarterback under center. It is a short-yardage and goal-line set for power runs: the fullback leads through the hole and either tight end can block down or kick out. Play-action from it draws the linebackers up and can leave a tight end open behind them.
Strengths4
Strength: Two tight ends and a fullback to block at the point of attack
Strength: Runs either way, so the defense cannot overload one side
Strength: Play-action pulls linebackers up and can free a tight end behind them
Strength: Strong short-yardage and goal-line formation
Weaknesses3
Weakness: One receiver split, so the passing game leans on play-action to the tight ends
Weakness: Tells the defense to expect a run, inviting eight or nine in the box
Weakness: Needs a fullback and two tight ends who can block