The benefit of using a scenario block is that you can write a scenario once and then use it any number of times without having to manually create instances of that scenario. Instead, in your main scenario, you define rules that create and manage the instances of the source scenario. When a main scenario uses a scenario block, the scenario block dynamically creates and manages instances of the source scenario according to the rules you define in the main scenario. The main scenario functions as a management tool for the sub-scenarios. This allows self-contained units of work that start and finish within the main scenario.

A main scenario can use several different scenario blocks. This lets you define multiple source scenarios, and then pull them together into a single main scenario.

Like all blocks, using scenario blocks makes propagating updates to the source scenario easier. For example, suppose you have 10 instances of a scenario. If you need to change that scenario, you must also update the 10 instances. Now suppose you have a main scenario that uses a scenario block to create 10 sub-scenarios. If you need to modify the source scenario, you only need to also update the main scenario that uses the scenario block.