Language, analysis and evidence have different limits

The iStar Guide defines a language; the PoEM 2009 treatment develops interactive modeling and forward evaluation. The ER 2010 procedure adds formal backward search with human judgements and backtracking under stated structural restrictions. The manual backward question used here is an adaptation, not an implementation of that algorithm. If a named solver is used, select compatible language and analysis versions and preserve their restrictions, rather than applying older propagation tables to iStar 2.0 without a justified mapping.

The subsequent systematic-versus-ad-hoc study gives reasons to attend to interpretation, coverage and training. It does not establish that a systematic procedure uniquely produces better understanding or more useful new questions. Use the model and its analysis for the contribution they can actually supply, then establish the domain evidence and decisions needed for reliance.