Vertical Concept - This concept is designed to beating certain defenses, i.e cover 2, cover 3, etc. It attacks the field in ways other plays don't by sending 4 men deep, and leaving one man underneath. Not to mention the way the routes are being ran. They aren't regular streaks that go straight. These routes are angled allowing it to attack the cover 3 in a different way where the safety has to pick which one he wants to guard, leaving the other slot streak open for an easy 15 yard gain.
In some of the shotgun variations, there will be a WR/TE running a post towards the middle of the field, beating man coverage since its a crossing route.
The HB works well in these plays too. In the under center variations, he's usually set to a delayed route, and in the shotgun variations, he's usually running some type of out route.
These are deadly when your playing an opponent who likes to blitz and he leaves a certain part of the field open.
leave the middle open=slot streak wide open. leave the flats open=HB running the out route. Also, if he's using man coverage, you can usually lead to the side the defender isn't on, i.e if the defender is guarding on the right, throw left and vice versa.