Agree. What's the fundamental property of distributed block building?
Arguably, it's how predictable inclusion is.
You could say that inclusion risk reduces to exogenous factors like network jitter.
So discretion is minimized, and builders compete on efficiency.
FOCIL provides this inclusion predictability for transactions the protocol can see in the mempool.
MPBC increases the inclusion predictability for transactions that are known to any builder, even if they are not in the mempool.