Design Validation - Decision Trees / Tables

Excel as means to defining rules. Nice move. Excel will be great for allowing all stakeholders to generate and implement rules. I understand some big clients like Copenhagen Airport are already providing consultants that work for them rulesets for them to use before submiting their deliverables. It would be good to provide a means to extend DV/Excel to generate decision trees / tables and other rules-based modeling tools. Python? Ex Bentley DesignPower's D++ also has a powerful rules-based engine that is already being used by PlantWise. ComplyPro also seems to have an Excel-like interface, maybe the rules can be exported to Excel?