@kinsella and I have exchanged in other channels regarding this.
For others, I will note that Hook has an API that could in principle be called dynamically from DEVONthink to detect whether the selected item has links. I suppose a DT label or tag could dynamically be applied. ( we could supply an alternative icon to designate the hooked state (perhaps Hook’s menu bar icon would do). ) I’ve asked someone here who uses DEVONthink more extensively whether such dynamic checks are feasible on the DT side. If nothing comes of that, we could ask a question on the DEVONthink forum. They would know best.