Farhi and Maggiori derive three different ranges of debt based on its magnitude. If debt is sufficiently low, the rest of the world will never expect the hegemon to devalue. Furthermore, if debt is sufficiently high, the rest of the world expects the hegemon to devalue with absolute certainty. Finally, there is an intermediate “instability" range of debt in which, under some conditions the hegemon has an incentive to devalue and other times does not. No one knows for certain. Thus, in this intermediate range, the rest of the world must simply assign some probability to its beliefs about devaluation.

Practically speaking, wouldn't we always be in the intermediate range? Because even if you agree with the model, you wouldn't necessarily know the parameters with certainty.