In the video, the instructor used 2 different diagrams to look for under allocated or over allocated costs. One is called the "Legacy Modeler" in the tool and is a vertical rollup of costs. The other is the Sankey diagram which appears to be the 'standard' or typical model diagram to use. The sankey is much more capable (e.g. drill down, selecting tiers, etc.) vs. the flat diagram of the legacy modeler. But are they showing the same data and totals (for roll up of costs), or are there situations where I might want to use the legacy modeler.