The simplest, and still best, route in all levels of football is the comeback. Almost impossible to defend, this play can open up huge pieces of the field for recievers to go deep later in the game. Just send the reciever 10 yards down field, have them turn and come back a couple yards. Unless the defensive player has super powers, he should't be making any play but a tackle after a solid gain. Using curls, comebacks, and quick slants in short-field situations opens up the long game, as d-backs are forced to play up closer, asking to be burned by recievers. And because they are playing so close to the recievers, the running game should get going up the middle.