Approval belongs in the data model, not the prompt

I want to be disagreed with on this one, so I will state it plainly.

Genuinely unsolved in my build, so this is more question than claim.

Two agents drafting against the same target. The pending-state model gives an obvious answer, last write wins, first draft discarded, and that answer is wrong in the case that matters: when the first draft was better and nobody noticed it was replaced.

Optimistic locking fixes lost updates but not lost judgment. You can keep a draft stack, but then the reviewer is choosing between branches, which is new UI and new cognitive load.

How are people modelling this? I am suspicious that the right answer is one agent per target, enforced by a lease, which is ugly but honest.

I am collecting cases where this pattern fails, so a counterexample is more useful to me than a vote.