Duct and Pipe New into Existing Workflow

When connecting a new duct or pipe to an existing duct or pipe, why does the length of duct or pipe that is removed with the new connection not show up as dashed in a demolition view? It simply splits the existing duct or pipe and removed the section where the new connection will be. Shouldn't this workflow be similar to placing a new door into an existing wall? When that condition occurs, the wall shows the area removed for the new door as dashed in a demolition view. Am I missing something simple here? :? Does anyone have a workflow for this situation? Just to note... This is all out of the box content in this example, including template, content and phase filters. (I was gonna upload example screenshots, but keep getting an IO error in the upload attachment dialog box)

Thanks for any help!!!