Since I started using Sonar Studio 8.5 I get this stupid "Missing MIDI Ports" dialog every now and then because I use USB MIDI interfaces.  When I select a new device to reassign I see nothing reassigned.  I'm now at X3e and it still does this -- I have to manually reassign the device on every MIDI track.  
 
Is this dialog supposed to adjust all of my MIDI tracks?  If not, what's its purpose and how do I reassign all of my MIDI tracks? 

To re assign all midi tracks:

When in the track view highlight all midi tracks by wiping down over the track numbers.

Choose the "Tracks" dropdown menu. It's in the silver area at the top of the tracks pane.
Choose "Selected track outputs..."
You can then re assign all tracks to the selected out.

Thanks, great!
 
Now, it would still be nice to understand the dialog because the tracks aren't all necessarily grouped together by output, so I have to peek at all the tracks and CTRL+click the ones that belong to the same output.  If the dialog worked the way I think it's supposed to I wouldn't have to hunt, and also would be less likely to make a mistake in track selection.

I think this is broke.  If I reproduce this by assigning a device to a track, then disable that device in preferences, the exact same dialog appears; when I choose a "replacement" device, the track is updated properly.  It doesn't work when this dialog appears during a project load.  It's been broken for all these years.