The work you do as part of a simulation is selectively, but not exactly, the same as what you would do as a lawyer confronted with a comparable problem. By drastically shortening the time frame of the actual process, the simulation allows you to experience the consequences of your choices relatively quickly. In a simulation, you are asked to assume certain roles, and to engage in a variety of tasks, some in-role and some out-of-role (except for the ubiquitous role of "law student").
Vanessa Merton, The Work of a CUNY Law Student: Simulation and the Experiential Learning Process, 37 UCLA L. Rev. 1195 (1990), available at http://digitalcommons.pace.edu/lawfaculty/164/.