The importance of knowing how to properly stack in a bunker is so crucial. The more players sharing a single bunker when shooting off the break can either look like a work of art or a catastrophe. It all takes proper communication, knowing the field, and timing to do it perfectly.
You'll notice teams normally stack two players in the back center to shoot off the break, but then other times you may see something as drastic as four of the five in the stack shooting. Once you start to stack more than two bodies in the same bunker you really need to fine-tune the positioning such as the depth and height of each player.
For example each time you stack two players you need to know who will be playing the tight position and who will play the loose position. Typically your loose player is the person looking to advance from the bunker to a side route or they will be the player that remains in that bunker the longest. The tight player will normally advance in a forward route up the center or they can be the last person in the bunker since they have the safety of the majority of the bunker.
A lot more strategy comes in to play when you stack any more than two players in a bunker. The tight player or players need to go in at a lower height, allowing the loose players to have the freedom to shoot above them and around them. The play needs to be decided ahead of time so you know which players are ejecting first and to where. The secondary players need to know what bunkers will be available so they can eject as soon as the window opens.
Stacking the bunkers is crucial to get the most eliminations and to increase the probability of killing a specific runner at times. Knowing the best lanes and largest threats will help you identify which lane to shoot and which bunker to contain.
You can practice these by doing breakout points and focusing one side on aggression and edge shooting vs a stacked breakout. Report to the coach any bounces, breaks, what worked, and what didn't work. Do 10 breakouts for just primary runs, then do 10 breakouts with the stackers making secondary moves, then do 10 full points mixing in the stacked plays with other plays to keep the opposing team guessing.