In one embodiment, a node in a computer network represented by a directed acyclic graph (DAG) may receive advertisements of smoothed path costs to a root node of the DAG, where the advertisements contain a field for a virtual gain factor (VGF) indicative of a difference between the smoothed path cost and an actual best path cost to the root. The node may then determine a local smoothed path cost from itself to the root, and also a local VGF for each link of the node (for the path as a whole including the particular link) based on all of the received advertisements and VGFs, as well as corresponding actual link costs (e.g., based on selecting alternative parents or actual link costs being smoothed within a dual threshold). The node may then compute a resulting smoothed path cost to the root along with an associated (cumulative) VGF based on the locally determined cost and VGF. Accordingly, the node may then advertise the resulting smoothed path cost along with the associated (cumulative) VGF on each link such that, for example, any node receiving a resulting smoothed path cost and/or VGF that surpasses a threshold may request a rebuild of the DAG (e.g., a portion or in its entirety).