This is especially important for performance testing. Because the SimUser can cover the full spectrum of complexity like a simple one line HTTP GET to something very complicated like E-Commerce / HTML5 validation, it is impossible to predict resource needs before the test starts. Avalanche provide you with real-time ways of determining bottlenecks. It is important to understand how to interpret these metrics because it will show you if you can generate more traffic at the same complexity, or backoff load due to tester congestion. In addition, it give you a mechanism for explaining to the customer when actual and expected load differentiates.