The triangular-term sign conjecture for constrictions

Let $(B,A)\in\mathbb R_{\geq0}\times\mathbb R_+$ be a constriction, and let $b$ and $c$ denote the two triangular terms in the corresponding transition matrix $Q$.

The triangular-term sign conjecture. The ratio of these triangular terms is negative, in the source's notation meaning

$$\frac{c}{b}>0.$$

The source first establishes that the ratio is real and then states this sign condition as a conjecture. A subsequent proposition gives positivity of a constriction under this condition, but the universal sign assertion remains open in the supplied text.