Playbooks

Doubles Flex is the balanced 11 personnel look inside Singleback that splits two receivers to each side with the tight end flexed off the line rather than attached in a traditional wing or tight alignment. That flex creates a true 2x2 picture with no reduced splits, so the defense cannot tip strength based on the tight end's hand placement. Compared to tighter Singleback sets that lean run first and force the defense to commit a box safety, Doubles Flex spreads the second level horizontally and forces the defense to declare its coverage rotation before the snap, which is exactly what you want when you are hunting a pre-snap read.
The alignment matters because your tight end becomes a slot receiver with a two way go instead of a blocker fighting off contact. Against base man coverage, that puts a linebacker or a slower safety on an inside receiver with clean space to work, and the Y Shallow Cross, Slot Cross, Inside Cross, and Flanker Drive plays all attack that matchup directly. Against zone, the same flex split lets you flood the hook and curl areas from two sides at once. Z Spot, Curl Flats, and Whip Ins all give you a settle route in front of the coverage while a vertical stem clears the safety.
The playbook depth here is what separates Doubles Flex from other sets in the formation. You get the full quick game menu (Slants, Double Slants, Double Outs), a real play action package (PA Dbl Posts, PA Y Glance, PA Deep In, PA HB Curl), verticals with Four Verticals and TE Post, and a legitimate run tree with HB Power O, HB Stretch, HB Draw, HB Dive, and HB Slam. Add HB Slip Screen as a blitz answer and the Gadget tag for motion and misdirection wrinkles, and this becomes a set you can live in for an entire drive without ever showing the same look twice.
Read the safeties first. Single high means attack with Y Shallow Cross, Slot Cross, or Whip Ins into the vacated middle. Two high means go outside with Curl Flats, Double Outs, or Flanker Drive to the numbers.
On third and medium, run Z Spot or Curl Flats and read the flat defender. If he expands, hit the settle route underneath. If he sits, throw the flat for the sticks.
Use HB Draw and HB Slip Screen against heavy blitz users, then follow with PA Y Glance or PA Dbl Posts once they slow down their rush and start playing the run honest.
Hot route the backside slot to a drag or in route on Four Verticals to give yourself a safety valve, and block the back to shore up the extra rusher against five man pressure.
Motion the Z on HB Dive Z Motion to identify man versus zone. If a defender follows across the formation, you have man and every crossing concept in the set is live.
Stay in the set for a full drive and mix HB Stretch and HB Slam with the quick game (Slants, Double Slants) so the play action shots hit later in the series.