When performing a duct mapping within the Duct Mapping dialog, both the destination pathway and the destination duct within the pathway are listed, so it is possible to immediately understand which duct is mapped to another duct:
When routing a cable over a duct within the Tube Box, the cable is automatically routed through the mapped tube pathway infrastructure and the user can continue the Cable routing process outside the Tube Box from there further manually throughout the Area (as the screenshot below shows), or finish the routing by a double-click.
During the cable routing process, auto-routing is applied based upon the connected tubes in the Tube Box. Specifically, special logic detects Tube Boxes and auto-routes the Cable through to the far end when going strictly through Tube Boxes (as compared to other types of maintenance holes). The reason for this special treatment is that, unlike in other kinds of maintenance holes, duct connections in tube boxes are guaranteed to be 1:1 and so routing is fundamentally simpler.
