Why concurrent generation changes the optimization

Additional swapping failures, memory decoherence, cutoffs, shared hardware, purification, and classical signaling delays can further alter timing and fidelity BrandCoopmansElkouss,LiCoopmansElkouss. They are not represented by declaring one independent exponential weight per geometric edge.

Consequently the engineered serial model closes its own interface, but the original unrestricted concurrent-network obligation remains unresolved. A restricted protocol's FPP cost is not an optimality theorem over all quantum-network protocols.