markers (1& 2) force to each other, trying to force the throw up field. The wall (3, 4 and 5) stop the down field cuts. and is generally slightly curved deeps (6 & 7) can either have short-deep and deep-deep or play left and right.
1 stops the up line cut. 2 forces back to 1, encouraging the up field throw.
If the dump goes to the middle, 1 stops the swing. 2 positions to stop the throw back (wise men say, "only fools rush in"). The wall blocks downfield options.
If the disc stops in the middle, 2 follows the throw in. And we are back where we were at the start.
2 stops the up line cut. 1 forces back to 2, encouraging the up field throw.
If the down field cutters get the disc, the goal of the wall is to stop the continuation down and allow the markers to catch up.
Markers catch up. 1 forces towards 2.
dump goes back. 1 stops pass back to 5 (i.e. doesn't charge in) 2 stops swing to middle.
wall takes cutters, 1 takes the mark.