Context
The support graph exactly predicts worst-case local splitting, but the graph invariant need not be efficiently computable when arity and the policy are part of the input.
Hypotheses and scope
- The support policy is represented explicitly.
- Arity is part of the input.
Proof or evidence
Membership follows by guessing compatible signatures. For hardness, assign one fresh letter and its three-participant support to every triple in a three-dimensional matching instance; policy signatures form a clique exactly when the triples are pairwise disjoint.
Verification notes
All 256 subinstances of the 2-by-2-by-2 three-dimensional-matching universe preserve maximum matching size under the reduction.
Limitations
- The hardness concerns policy-only worst-case prediction, not enumeration once a fixed canonical product is already explicit.
- Three-dimensional matching hardness is classical; novelty is only claimed as plausible for this Boolean-product application.