I have seen a big of discussion about using the vertical passing game to open up the run game more in JoMo's offense by keeping opponents from loading the box. But I thought that was what the spread was designed to do.
You have a QB/RB in back field and 4 WR's occupying their defenders out wide. That gives the defense 7 players to defend runs near the LOS. With a drop back passer that is historically 7 defenders in the box against 5 OL blocking so they out number you by two, who are free to make a tackle. If you have a QB with a RPO, then that evens it up inside because the RB becomes a blocker and the QB either has to make the remaining Guy Miss and if the run isn't there throw to a WR. Maybe I am missing the design of the RPO in the spread offense.
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You have a QB/RB in back field and 4 WR's occupying their defenders out wide. That gives the defense 7 players to defend runs near the LOS. With a drop back passer that is historically 7 defenders in the box against 5 OL blocking so they out number you by two, who are free to make a tackle. If you have a QB with a RPO, then that evens it up inside because the RB becomes a blocker and the QB either has to make the remaining Guy Miss and if the run isn't there throw to a WR. Maybe I am missing the design of the RPO in the spread offense.