Can Bus Volume be automated ?

TimV
I really like your idea of putting even a single track into a bus to adjust the mix volume without affecting the track's automation. I guess it can be with gain, but I like this better, being able to use the fader. Thanks for sharing it.

Konrad has described a useful technique, for sure. But it sounds like you may not aware of Offset Mode, which can change track volume without affecting a track's automation. If you group multiple faders, you can use Offset Mode to vary all of them simultaneously without have to use a bus.
 
But I will say this: I think the next update is going to blow some minds when it comes to tracks, buses, and mixing...

An easy way to get "there" with any automation is to simply click the "W" - for "Write" in the mix window (console view) - and then manipulate the channel strip - volume - pan - etc.  This is helpful in my experience  as sonar automatically creates an envelope for the parameter you want to manipulate.  Say - you want to add a high shelf to an eq on your guitar buss - but only for the chorus.... click the W - open the lug in and just click and drag the eq in real time and sonar creates the specific envelope for you.  There are times in a mix when I will want to do a complex effect manipulation - like for example - on the last note of a rock star guitar solo - lengthen a decay time of a reverb, while also increasing the intensity, spread, and mix of it.   For something complex like this - its super easy in sonar:
 
Go to the last note - arm the "write" feature - open the reverb plug in - press play and simply click on each of the controls I want to manipulate - in this case - decay, drive, spread, and mix.  Sonar creates each of these envelopes individually, Ill then loop the section of the audio and go back in and fine tune the effect automation.  
 
MAKE SURE YOU TURN THE WRITE COMMAND OFF so you dont dig yourself a hole=-)