Some examples of handler movement and overloading defenders against a trap zone like Pommy.
HANDLER MOVEMENT TO GET A DISC OFF THE SIDELINE. If the disc is trapped on the sideline, easiest option is to give the dump a throw straight backwards, and look for the swing to the third handler straight away.
If the mark overcommits on stopping the backwards pass, a pass straight across to the third handler should open up.
Alternatively, a popper can come from behind and pop through the cup...
... and attempt to pull it out of shape
Providing an opening for an easy dump or a swing pass directly to the other handler.
OPENING UP SPACE THROUGH THE MIDDLE. The poppers can work together to shift the defense and open up space for each other.
One popper makes an obvious (and preferably loud) cut to one side of a defender - in this instance 4, who will naturally move to stop that option.
The other popper can position themselves behind the hole that opens up, allowing a relatively easy pass through the middle of the field.
The same thing works on wing defenders.
One popped cuts right by the wing defender, dragging them out of position.
The other popper slides into the space that opens up.
Finally, there will be lots of times where the third handler on the open side is left alone while the wing defenders worry about the poppers.
The handler on the open side should take as much ground as possible on the easy swing pass.