In order for a company to achieve sustainable success, its management control framework must be able to coordinate a diversity of decision makers, each with different business management skills and individual goals in differing business situations. This is the only way to ensure that dealings are coordinated across the company as a whole. This limits significantly the permitted level of complexity of the metrics used, but complex calculations are generally not suitable for management control decisions anyway.
Controllers need to systematically divide their toolbox into tools for decision making and tools for coordination. In the hands of a small group of experts, there is an advantage in using sophisticated tools to examine every question in fine detail. If, however, the results of the analysis are for coordination purposes, they require explicit transformation: Technical language has to be put into more colloquial terms because coordination requires everyday language rather than technical jargon. If the translation is inadequate, not even a call to simply trust the experts will help in the long term. Managers will not accept what they do not understand. For them, a "black box" is not an option.
In the end, controllers are going to have to live without going into the minute detail of management control. In this case, a healthy dose of pragmatism is less hands-on than he is generally presumed to be : it requires a more realistic assessment of what managers are cognitively able to achieve given their workload, and on what they want. The primary aim of controllers should be to increase the quality of coordination; in most cases, this is probably far more advantageous than aiming to provide better support for decision making.