The PointErrors and LineErrors feature classes provided a simple way to analyze and address UN errors via SQL and Python. Each record provided a single error code and identified both features involved in the issue. The UN4 approach is a serious barrier to effective automated error analysis. I think the least that can be done to rectify this situation is to provide geoprocessing tools to generate the old error classes. Given some reflection and imagination, think of the even better tools that could be created.