Let's start off actually looking at another play that Iowa runs from time-to-time: All-Hitches. Depending on the protection and the drop, this play can be run anywhere from 5-12 yards depth. On the sorter end (All-Hitches), it's more about flooding underneath coverage and quickly getting the ball out into the voids of coverage before the coverage can get into their coverage. On the deeper route concepts (All-Curls), it's more about threatening vertical and finding the voids between levels.
Because the way defenses react to condensed formations, the TE-Wing combination can be an effective way of to stress on this vertical come-back routes because defenses generally constrict to match the condensed formation, and then coverage requires more movement to return to their coverage zones (also helping the QB identify potential voids).
Now let's specifically look at this play. First, the formation.
I love formations like these, with the TE-Wing to the short side of the field and an offset RB in their direction as well. It effectively creates a tight bunch without the defense treating it like a tight bunch. This means they aren't running their banjo coverage or whatever else, they may play an in/out or high/low on the two TEs, but they are limiting their coverage because it isn't recognized as a bunch.
Creating bunch without actually being in bunch is my life right now— Seth 'Nervous Bird' Galina (@SethGalina) September 26, 2018
Agree, Seth. Agree.
To the far side of the field, the WRs motion into a stack which will help identify coverage and help with the underneath receivers release.
As I stated, upon the snap, this play is going to look a lot like all-hitches. The TE then settles (just as he would on the comeback route) at 10-12 yards, before breaking inside and pulling the safety with him. With the RB releasing into the flat, you now have a high-low on the CB down the near sideline (it being the near sideline similarly allows the pass to get to the receiver quicker, which makes this harder for the conflicted defender, particularly with his inside safety help pulled away).
From the wide side, the underneath receiver is going from his stack and dragging across the field. This effectively helps form a triangle for the QB, with the two low options being the RB in the flat and the dragging WR. If the CB maintains depth, then the QB will read the OLB to the shortside and throw away from his movement (stay inside, throw RB, move outside in coverage, throw the drag with a WR on an underneath LB in space).
If for some reason the drag is also covered, there is a levels concept over the middle of the field, and the deep TE running the Dig is likely running into space because the X-WR is pulling coverage with him on his Go route.
Here's what it looks like:
What's nice here is the timing. The first high-low read is relatively quick, as soon as the Wing gets to about 12 yards, the QB has his read of the CB (light blue box). The drag comes a little later, so there is natural progression to move to the next movement key (dark blue box). And as a last resort you have the big TE that can box out safeties.
Here's the clip:
One couple things to point out. The dig is going to be a feel thing, it's not a hard crossing route, so notice the TE is winding down a little bit at the top of his route and working a bit back to the ball. This is because he doesn't want to run into coverage on the far side (the Cover 4 safety stays home as the drag is passed off to the LBs).
Another thing is the wheel route. Because the short side safety is sticking to the Dig route, the Wing knows he doesn't need to stay glued to the sideline for spacing. So he starts to work back to the middle of the field like a post. This gives the QB more time to make the throw, more room to make the throw, and in general is an easier throw to make.
It also isn't particularly difficult to build off this play with a swing screen. If the defense starts capping the vertical routes, utilize TEs vs DBs blocking and let the RB attack LBs in space. If you can find a way to get an OL releasing downfield as well, you have it all blocked up.