I think there is an RPO x 2 (Min.) offense that can be run without spreading the defense.
Maybe it should be called a RPOPO.
The idea is to read keys in a congested field & get the ball either forward or backwards to another player who is also reading keys.
receiver routes are set ups to putting defenders in positions where their momentum has less leverage than the offensive player.
RPOPO = run pass option / pitch option based upon the observation that all defenders abandon their coverage responsibilities once the ball crosses the line of scrimmage.