A primary difference between the two methods is the degree of formality. Whereas SAAM is based on an informal representation of the entire architecture, Easterbrook and Nuseibeh use semi-formal state representations and reduce complexity through partial specifications. However, neither method provides a quantification of view interdependencies relevant to system architecture evolution. Such a measure would provide insight into the ramifications of proposed system evolution plans. The second critical barrier is conflicting stakeholder goals.
Conflict resolution is essential if the system or software architecture is to be developed at all.
The most significant work in this area is Boehm's Win-Win technology. Architectural decisions are made based on quality attribute trade-off models and documented through rationale capture. The shortcoming of Win-Win represents the third barrier to achieving consensus, a lack of objective measures to quantify costs and benefits of a product line given specific architectural choices. The QAC approach provides greater visibility into the architecting process by quantifying architectural choices based on strategic cost-benefit goals and provides immediate feedback concerning financial viability of architectural choices. The QAC draws on marketing theory and consists of choosing the attributes of an architecture in such a way as to maximize the attainment of required cost-benefit goals.