Ok, with midi channels under control, new issue:   I have CC1 controller data set as channel 1 in one track, and CC1 controller data set as channel 1 in another track.     Both tracks happen to go the the first midi track in two different VSTi instances.    Let's say, viola doubled line going to two different libraries, loaded into two Kontakt instances. 
 
Keeping things simple, midi channel 1 for the events matches midi channel 1 for VSTi synth 1 and midi channel 1 for the events in the other track matches midi channel 1 for VSTi synth 2.   There are only 16 midi channels, so some duplication of channel numbers is unavoidable, and it is easy to put both violas in channel 1.    
 
Now, however, load both viola lines into a PRV window.      I want to do some controller drawing, to balance the sound from the two libraries I'm using.    Alas: because of the way the controller pane is designed, it is not possible to see both controller CC1, channel 1, lanes at the same time.    If I switch back and forth there are ghostly indications for both tracks, IN THE SAME controller lane.   Although I've certainly complained often enough about not wanting to see tens and hundreds of controller lanes in one PRV pane, in this case I DO want to see two distinct lanes, with track 1's CC1 data visible, and selectable, and track 2's CC1 data also visible and selectable.  
 
Bottom line:   'channel-based' controllers in the 'track-based' PRV is a big design mistake, please fix it.    

williamcopper
I want to do some controller drawing, to balance the sound from the two libraries I'm using.    Alas: because of the way the controller pane is designed, it is not possible to see both controller CC1, channel 1, lanes at the same time.

Two options:
 
1. Temporarily change the channel of the event data for VSTi 2 using Process > Find/Change. The forced MIDI channel will ensure they play correctly, but the PRV will show controller data in separate lanes.
 
2. Balance the sound with your ears instead of your eyes.
 
EDIT: Another option: You can slightly darken the gray level of the PRV Window Background so that ghosted controllers show up more clearly. At least that way you can more easily compare controller levels between two tracks. But you'll still have to switch focus to edit one or the other. Note you might also have to adjust the gray level of Grid Rules (i.e. secondary gridlines) so they contrast correctly against the new background. I experimented, and just lowering the background level from RGB, 241,241,241 to 221,221,221, and Grid Rules from 208,208,208 to 198,198,198 worked pretty well without totally messing up the appearance of the PRV.
 

Thanks.   As to opt 1, yes, that's a work-around, but rather time consuming ...
 
As to opt 2, it's my ears that tell me I need to adjust the controllers.   Or do you mean try to push the mouse around with one ear?  Got enough neck pain already, thanks! 
 
Here is the practical thing I'm trying to accomplish:  three snippets, different viola libraries (VSL Chamber Strings, Berlin Strings, 8Dio Adagio Strings); the combined versions clearly sound better than the single-library versions, but sometimes adjustments are needed. 
 
https://soundcloud.com/williamcopper/sets/viola-work
 

williamcopper
Bottom line:   'channel-based' controllers in the 'track-based' PRV is a big design mistake, please fix it.    

All design choices make compromises, and changing them has consequences. Since tracks can contain events on different channels, simply doing away with channel-based controller lanes is not an option. It seems to me that what you really need in this case is the addition of per-port differentiation, but that's not going to help with the lane-proliferation problem.
 
In any case, "please fix it" is not a meaningful or helpful. You're going to have to do a much better job of describing the exact functionality you want in various scenarios, and enter it as a Feature Request.
 
In the mean time, if you really want to wait for the Bakers to introduce Copper Editing Mode, you're welcome to do that. But since you posted in the main forum, I thought I'd give you some suggestions that might help you actually finish editing your violin tracks in the near term.