It would be convenient if Sonar had the ability to automate a "send enable" for a channel's send to a bus or aux track. It would be much easier to write automation by simply clicking a button to enable or disable a send rather than having to manually automate the level of the send.
 
Thanks.

What I noticed recently is that enabling/disabling a send during playback introduces a slight delay (depending on the plugin or soft synth used, I think) in the bus channel the signal is sent to, so I would still automate the send level even if the send on/off button became automatable.