The best way to take advantage of the Pareto principle and Parkinson’s law is through reverse scheduling. Reverse scheduling refers to starting with a project due date and scheduling backward as opposed to forward scheduling which begins with a project start date and you work until it is complete. This is a subtle but important difference. The things that you want to do (defined in your pie chart) are the things that you schedule first. The things that you have to do but are not necessarily high impact can fit into other places.