Constraint based system is efficient for static input. But it is inappropriate for incremental revision support under dynamic constraints and preferences because of static input and tight integration of problem solving algorithms.
In the 1994 CAIA "Workshop on Coordinated Design and Planning", participants were asked to present systems that solved the "Secretaries' Nightmare" problem. However, no system solved it completely, largely because the problem includes several incremental revision steps due to constraint or preference changes. The conditional nature of the extra meeting constraint was particularly troublesome because of lack of support for managing changing constraints and variables that may apply to a particular way of solving the problem or changing circumstances. And there was no provision for remembering earlier solutions that could be reapplied under changing conditions