First, lets see what happens when a cutter doesn't clear properly.
Everyone is set, and the first cutter starts his cut
First, an example of how not to clear:
Here, player 7 gets looked off and tries to get out of the lane, however the defender doesn't have to follow him deep in this situation because #6 is last back
So now when player 7 tries to get out of the way, the defender can just sit in the lane and take away the open side.
When player 6 starts their cut, this becomes obvious; there's no open throw. Even if player 7 continues deep, it is a very tough throw to put the disc past so many players. With any wind, it becomes almost impossible.
Now let's reset everything and see how the offense SHOULD look..
Player 7 makes their cut and gets looked off..
But instead of a lazy jog up the sideline, they make a hard cut to the front of the stack, opening the lane for a new cutter.
Player 6 now has room to make a cut into space and if he beats his man, then it should be an easy throw to advance the disc.
Let's take a step back.. what if player 7 cuts to the front of the stack, and his defender sits in the lane anyway? This is called poaching, and it's a bad habit when you're playing defense. The next few plays will make this clear:
This is lazy defense and when recognized will easily be beaten. Player 7 should scream at the man with the disc "POACH" and cut over to the break side.
Because there are no defenders on that side, even a floaty, less than perfect throw will find the open player 7.
Because the defenders are now on the wrong side of the stack, a cut from the back to the endzone will be very difficult to defend and will often result in a point or at least some serious yardage. Additionally, player 7 will not have a mark since his man was poaching the other side of the field, meaning that it should be relatively easy to put up a big throw.
Let's reset the stack and address another common issue: the location of the stack.
Let's suppose that players 3 and 4 have already made cuts from the back and cleared back into the stack. The stall count is getting high, so player 2 dumps the disc to the other handler, player 1.
What would happen if the stack didn't move? Based on the position of the defense, there are now no easy throws for the man with the disc. To maximize the space available, the stack needs to rotate.
Now that the stack is diagonal, there is both an open side lane and a break side lane, just as when the disc is in the center of the field.
Here, player 6 makes a break side cut and player 7 cuts open side. The disc goes up to player 7.
Player 7 now dumps the disc to player 2, who ends up on the right sideline. Notice that everyone is clumped together in the middle. How should the stack reset?
If you guess that it should rotate again, you're correct. This once again creates the open and break side dynamic which makes the vertical stack effective.
And then of course, resume as you would normally, cuts from the back..
And score lots of points.