The design choice
A single-number comparison is a single point of failure.
Reduce the comparison to one figure and the review inherits every blind spot that figure has. Equity ahead of model is the obvious candidate and the worst one, because it is satisfied by outcomes the system exists to prevent: risk taken beyond authorisation, overrides used as habit, a branch mix drifted toward variance. The stack's answer is redundancy of a specific kind — not five measurements of the same thing, which would merely be reassuring, but five measurements that fail for different reasons. Expectancy can be strong while drawdown is abnormal. Drawdown can be clean while conversion is wasteful. Each row is a different question, and their disagreement is the signal.
Schematic exposure score: how much a strong reading on this row alone can conceal, judged by how many other rows would have to be checked to rule out the flattering explanation.
