Adaptive depth gating is a per-query controller that sets the ancestor traversal depth $d_\uparrow$ and descendant traversal depth $d_\downarrow$ as a function of the hierarchy level $\ell(v^\star)$ of the top dense seed and the dense-score contrast $\Delta = s_1 - s_5$ between the top and fifth dense scores. From base depths $d_\uparrow^{(0)}$ and $d_\downarrow^{(0)}$, the controller adds an indicator when $\ell(v^\star)$ is high (pushing $d_\uparrow$ up) or low (pushing $d_\downarrow$ up), and adds an indicator when $\Delta$ is large (more upward depth) or small (more downward depth), with floors of $1$ and $0$ respectively. Across the studied benchmarks (LectureBank-Full, QASC, HotpotQA boundary probe), adaptive gating remains statistically tied to a fixed-depth hierarchical baseline once interfaces and splits are matched, so it is treated as an optional extension rather than a core claim.