This is not an issue restricted to PowerDraft. With any version of MicroStation, certain tools can remove the user data that InRoads attaches to elements that it uses to identify them as InRoads elements.
However, the design information is still saved in the geometry project or the dtm or the roadway designer files.
If you are only moving text around using basic tools, there should not be an issue. But if you start copying elements, things can be retained that makes InRoads treat the copies as elements it created.
I've seen and heard of people copying a centerline parallel to create their road edges and sidewalks and other parallel linework and then someone needs to change some small item related to the original centerline and InRoads grabs the whole mess and erases it in preparation for displaying the revised centerline.
Some offices have working InRoads files and copy that data into other files to create their sheets to eliminate that issue, but that just opens up the whole version world.
Using MicroStation since...