Hi Andy
That is an option and I do sometimes do that but often I dont always want to work in automation gain mode.
You can also use loop play as another method of doing this so the ability is there.
The fact I am adjusting the level means I want to hear it so I can't think of a logical reason for the timeline stopping in the first place other than perhaps it was a limitation of earlier hardware.
Imagine what a Protools mixer would say if the timeline stopped every time they made an adjustment - it would be a non starter.
best wishes
Neil
http://www.patience.tv