It has been shown that the SysML PropertySpecificType strategy suffers from many disadvantages. While it admittedly does offer the greatest possibility of redefinition of default values, operations, and constraints, it is fundamentally subject to inefficiency both in modelling and diagramming, primarily because of the "cascading" effect of the implied subtypes of an existing complex assembly. It also presents problems for reuse of existing typed connections between parts.

If we are just interested in deep re-configuration of a complex assembly, or in statement of its evolving "value state", an alternative offers itself. We may use a ValueSlice strategy, which manages a list of InstanceSpecifications, the Slots of which can be mapped efficiently to a values compartment of parts in an IBD for a specific "value slice" usage context of a complex system. The MD SysML team is now working towards practical deep value assignment suited to real-world systems engineering leveraging this technique.